First, addressing the question of length - it took me about 125 hours to
finish Persona the first time I played it. I'm guessing because the game's
built-in clock stopped at 99 hours and 59 minutes when I was in the
second-to-last dungeon. The second time I played through it, I already had
all of my maps & was more familiar with the game, so it only took me about
40 hours. In comparison, it took me about 70 hours to play my way through
Wild Arms (stopping to find every secret I could, of course), though it
would've taken a lot longer if I didn't have a strategy guide to help me
with the more frustrating puzzles (don't even talk to me about the
floating diamond puzzles in Dhee's tower... argh!)
Persona has become my all-time favorite RPG. It has earned this
distinction because, out of all the RPGs I've played, it was the *only*
one that was so good, as soon as I finished it I wanted to turn around and
play through it again. And that's exactly what I did, even though a
brand-new, unopened copy of Wild Arms was sitting next to my Playstation.
I'll probably play Persona through two more times before I'm done with it.
Wild Arms is an excellent RPG, and I did enjoy it, but there is no reason
why I'd want to play it through a second time.
What gives Persona such replay value is that its combat system is so
complex. Between all the myriad Personas you can create, and negotiating
with all the demons (especially when they take it on themselves to start
talking to you!) there's simply no way you can see and do everything in a
single game. There's also the fact that you get to choose one of four
different people (Brad, Ellen, Alana, or the secret char Chris) to be the
fifth member of your party, and whoever it is will add his/her own take to
the storyline. 
But anyway, compare this combat system to Wild Arms. Sure, WA has pretty
polygon monsters (and guardians - the Life Guardian was my favorite), but
compared to Persona the combat is simple and boring. 90% of the time, all
you do is whack the monsters with a sword, gun, or maybe a spell (and 75%
of the spells in WA aren't worth the effort to cast them). Killing the
bosses is nothing more than whipping out all your most powerful attacks
and beating ‘em into submission - and maybe throw in a Lock State spell to
keep yourself safe, healing stuff to keep yourself alive, or 99 Goat Dolls
if you're up against a really tough enemy.
In Persona, the magic system alone depends on summoning any of a hundred
different Personas to cast spells for you. The same spell looks radically
different depending on whether an angel, devil, god/godess, or
mythological beast is casting it. Furthermore, magic use is encouraged
because Personas get stronger the more spells they cast, and you
automatically regenerate spell points while you walk around (no mind gem
or whatever required). It isn't until late in the game, when you're
casting high-powered spells that cost a huge amount of spell points, that
you really have to worry about running out of magic power. 
Furthermore, the formation of your party affects combat. You have to
figure out how best to arrange your party, and what spells or weapons work
best at what ranges. Sometimes, you'll be ambushed by demons, and have to
fight with your formation reversed. BTW, a quirk of the combat system is
that experience points aren't evenly divided - each char gets experience
based on what he or she did in a fight. A char who just defends gets very
little experience, and if you want a char to get lots of experience, have
‘em cast Heal All in a fight (even if your party is in perfect shape!)
Another strong appeal of Persona is that you influence the storyline. I
don't know why anybody bothers to ask you a question in Wild Arms, your
answer never makes a difference anyway. But in Persona, there are two
endings (a good one and a bad one), and the answers you give determine
which ending you get. There are also several times where your choices
don't seem to have a impact in the game, but if you last long enough, you
will eventually have all your decisions thrown back in your face. 
Persona's storyline itself is very gripping, dark, and original. It's set
in the modern day. You and your friends are normal high school students,
when a sudden invasion of demons overruns your home town, cutting it off
from the world. Just when it seems like you're going to be slaughtered, a
new power emerges from your soul - the power of Persona. It's up to you to
use this power to survive, find out what is causing the mayhem, and put
things right again. If you're like me, you've played "save the princess"
and "save the kingdom" RPGs more times than you can invent a metaphor for.
The characters in Persona come across as well-developed and real; darned
if I didn't know these people, or students like these people, back in my
old high school. The exception is, of course, the main char (you :) whom
*you* develop based on the choices you make.
Other details... graphics are nice in that there is *none* of that
super-deformed rot that infests Wild Arms, et. al. The dungeons, all seen
from a first-person perspective, look virtually 3-D and are very nicely
done. The character interface may seem confusing at first, but it soon
becomes easy to work with. The characters and monsters are pretty
well-animated, and you get to see them all wave their arms to cast a
spell, or run up to attack, etc. The figures are pretty small in the
combat screens, though. Outside of combat, most major chars (player chars
& NPCs both) have an anime-style profile that pops up when they're talking
to each other. I *really* like the sound effects, whether it's the sound
of your shoes on the floor, demon's outcries (in Japanese - if you watch
enough anime, though, you can usually figure out what they're saying :),
or best of all, our heroes' battle cries. I mean, good grief, ever notice
that the heroes of Wild Arms are *dead silent* throughout every fight? But
in Persona, there is probably no single little detail I like more than
hearing the main char yell "Eat THIS!" whenever he opens fire with his
machine gun. ^_^
The music is very powerful. More than the music of any other RPG I have
played, Persona's music does a superb job of capturing the feel of its
settings, whether it's the busy high school (you can hear the student
chatter in the background), the spooky haunted house, or the jazzy
underground palace of the Harem Queen. I'm a little biased toward
Persona's music because most of it is techno with a fast beat, my favorite
kind. The music is not as outright "beautiful" as some of the music in
Wild Arms, or even Beyond the Beyond, but then, Persona is a much darker
game in a much more eerie/horrific setting. The Sebec basement sirens had
me on the edge of my seat, and the growling of Avidea World was
pulse-poundingly ominous. None of the music in Wild Arms ever had that
kind of effect on me (though I guess the "we've figured out how the
monsters bypassed the town wards" music came the closest.) Heck, I've
tried to order an imported Persona music CD, and I'm still waiting for it
to arrive (I think I'll blame that on the UPS strike. :) The only flaw is
that you have the same combat music for the entire game (except for bosses
- but there aren't very many of those). It does get a little tiresome
after a while. (Wild Arms also shares this flaw. Beyond the Beyond does
vary its combat music, but it freakin' well ought to, seeing as how you
fight something every 4 steps anyway...)
Persona is not the RPG for everyone, though. IMHO, its single greatest
failing is the lack of puzzles. There is only one real puzzle in the game;
everything else is just navigating mazes, surviving monsters, and
storyline. In fact, I was rather disappointed when the final dungeon just
turned out to be one loooong maze... there weren't even any side rooms
where you could talk to your party members, something that added flavor to
virtually every other dungeon (except the Ruins, but that's an optional
dungeon just in case you want to go back and face certain demons). Compare
this to the interactive puzzles in Beyond the Beyond, or the cornucopia of
easy-to-diabolic puzzles in Wild Arms, and it's a minus.
Other folks, such as the earlier poster, complain that Persona's mazes are
long and tedious, with too much combat and too few save points. Hmph. I
think that the first-person perspective is helpful because it greatly
simplifies mapping (you take one step forward, you mark one square on the
graph paper), and if that weren't enough, you also have the automap,
including a small cross-section constantly displayed in the upper screen
corner, to help you out. I think it's fun to map out and navigate a maze
(almost a puzzle in and of itself), and the only dungeons that seemed
tediously long were Deva Yuga and Avidea World (the final dungeon). It
helps a great deal that you regenerate spell points, so that if you're
strong enough to handle the monsters, you can usually trek for a long time
before you run low on power. One weakness, though, is that Persona lacks
any kind of "return" or "escape" spell to bring you back home to the
closest save-spot. Unlike Wild Arms, Persona doesn't have save-spots
halfway through its dungeons, or just before the boss. The best you get is
at the beginning of a dungeon. A couple of the longest dungeons do have
trap doors that will take you quickly back to the beginning, but you have
to find them on your own. If your entire party dies, you have to start
over from when you last saved, so you do want save with moderate
frequency. 
Someone said that you can go for five hours between save points in
Persona. Well, if you want to conquer Avidea World all at once (and you're
not relying on the maps in the strategy guide, of course), then it
probably would take at least five hours to work your way through the whole
mess. What I did was map each of Avidea World's eight sections separately
- every time I finished a section, I'd double back to the beginning and
save my game, then recharge and forge ahead to the next section. The only
time it took me five hours between saving (four and a half, actually) was
in the Harem Queen's palace, and that was only because I was too stupid to
recognize the elevator. ^_^ 
Also, with the possible exception of bosses, survival is pretty easy as
long as you're careful. If individual chars die, they're revived at the
end of combat with 1 hit point, so you only have to worry about your
entire party being wiped out. You have to develop Personas with the Heal
All spell (the Halo Persona is indispensible), use the built-in Analyze
feature to determine the most dangerous enemies, and decide which attacks
are best against them, etc. (Unlike the Wild Arms Analyze spell, Persona's
Analyze is very thorough, telling you what spells a demon can cast and
what its strengths & weaknesses are. You don't even have to cast a spell
or use a combat action. You just have to defeat one of that specific
demon's kind in combat first.) Though I had a few close calls, my Persona
parties were never actually wiped out. This is more than I can say for
some RPGs, where if the computer really, really wants to kill you, you are
dead in a ditch. (Final Fantasy for the NES comes to mind - ever meet four
dragons who get first strike and all decide to breathe fire on you?)
To summarize: rent Persona first if you're not sure, but I loved it and it
will probably stay my favorite RPG for years to come.
Victar, DNRC Minister of Obsessive-Compulsive RPG Addiction
       Bard's Tale I-III * Might & Magic I - Swords of XEEN 
   Dragon Wars * Swords & Serpents * Shining in the Darkness 
Arcana * Don't Go Alone * Drakkhen * Final Fantasy NES - Mystic Quest 
  Beyond the Beyond * Persona * Wild Arms * Dragon Warrior I
"Stupid people can be happy when ruled by smart people!" - Nate, _Persona_