Here is a complete list of all the games posted in this thread that have been tested:
(If there is anything I have missed or anything that you beleive is incorrect let us know and I will change it)
(Any game you post in this thread I will add to this list)
(Last Updated: 09/08/2011)

Bloody roar 2 (Sound Problems)
Breath of Fire 3 (Rendering Problems on various Magic animations crashes game)
Crash Bandicoot 3 (Working)
Dead or Alive (Working)
Dino Crisis (Limited Testing - Working)
Dino crisis 2 (Working)
Dragon Ball Final Bout (Working)
Final Fantasy VIII (Working) (Note: Make sure all video enhancers are on. Try not to load from save states it seems from my experience to mess with cutscenes sometimes. Load properly from memory card whenever possible!)
Future Cop LAPD (Working)
Gran Turismo (Working)
Gran Turismo 2 (Working)
Hogs on war (Working)
Jade Cocoon (Working)
KKND: Crossfire (Working)
Magic the Gathering: Battlemage (Working)
Marvel Vs Capcom (Working)
Metal Gear Solid (Working)
Monster Rancher 2 (Working)
Music 2000(Sound Problems)(The majority of the sounds for this game will not play. As far as I know the sound driver is not on the todo list. So this game cannot be played until a better sound driver is added to the emulator. So its just a waiting game.)
Parasite Eve (Working)
Parasite Eve 2 cd1 (Working)
Populous the Beginning (Working)
Poy Poy (Working)
R-Type Delta (Working)(Note Crashes When all lives are lost)
R-Types (Working)
Resident Evil Survivor (Working)
Resident Evil 2 Leon Disc (Working)
Resident Evil 3 (Working)
Ridge Racer 4 (Working)
Silent Hill (Sound Problems)
Sim City 2000 (Working)
Soul Blade (Working)
Street Fighter Alpha 3 (Working)
Syphon Filter (Working)
The legend of dragoon (Limited Sound Problems)
Tenchu (Working)
Tenchu 2 Birth of the Stealth Assassins (Working Limited) (rconnor33: Plays excellently but freezes briefly on all stealth kill animations... this is VERY annoying and if anyone knows of a solution I will forever be in their debt!)
Tekken 3 (Working)
Tony Hawk Pro Skater 4 (Working)
Unholy War (Working)
Vagrant story (Sound Problems)
Warzone 2100 (Working)
Wu Tang: Taste The Pain (Works but crashes at the end of every fight)

Before posting feedback ideally make sure you have tested the game with all aiding features on. Xperia Play has a good processor and can handle it
Settings:
SPU Sync ON
Everything in system except HLE and Boost turned ON.
Video Frame Limiter ON
Enhanced 3D Rendering ON
Sharp Overlay Drawing ON

Ill add my 2 cents


Final Fantasy VII - Runs Great but with odd sound

Tekken 3 - Runs Great but laggy sound

Resident Evil - Does not run only get a black screen

Resident Evil Directors Cut - Does not run only get a black screen

Street Fighter Collection (Disc 1) - screen off centre makes it quite unplayable

i will keep adding as i try new games

Hi all, im new here.

Edit3

I tested

Silent Hill - No sound on any video and no voices sound during gameplay.

Dragon Ball Final Bout - Perfect.

Bloody roar 2 - Sound lag problems.

Parasite eve 2 cd1 - Perfect.

Dino crisis 2 - Perfect.

Vagrant story - Sound lag problems.

The legend of dragoon - Few sound problems.

Resident evil survivor - perfect (how to move using gcon mode???)

Hogs on war - Perfect.

Crash Bandicoot 3 - Perfect.

I'll edit when I test more games...

If you dont have my problems, please tell me how.

I'll add my confirmed games list here to add to the ever-increasing potential of the PLAY:

- Final Fantasy VIII Disc 1: Loads OK and plays FMV intro without a hitch, but haven't bothered to play to a fight yet - was just checking it loaded OK.
- Tenchu: Perfect with no issues.
- Dino Crisis: Fine so far but haven't played for long.
- Street Fighter Alpha 3: Plays perfectly with only a rare music glitch here & there.
- Parasite Eve: Perfect so far.
- Resident Evil 2 Leon Disc: Perfect.
- Resident Evil 3: Perfect.
- R-Type Delta: Crashes when you lose all lives but perfect otherwise.
- R-Types: Perfect so far.
- Soul Blade: Odd music glitch but otherwise perfect.
- Syphon Filter: Perfect so far.
- Music 2000: sound totally FUBAR (thereby defeating the point!)
- Tenchu 2 Birth of the Stealth Assassins: Plays excellently but freezes briefly on all stealth kill animations... this is VERY annoying and if anyone knows of a solution I will forever be in their debt!

Hi All...I've been playing Nectaris: Military Madness and it works great on version 0.10.48. Runs at a constant 60fps on the Xperia Play. No graphical glitches whatsoever. Music has a slight intermittent slowdown in some of the cutscenes. This is a sequel to Military Madness on the Turbografx (Nectaris on the PC Engine in Japan).

update: When using fpse's save feature (not the memory card), loading the state will cause the map to be blacked out. It comes back after a fight scene though.

Note also my testing:

Gran Turismo: perfect (only the first menu is off center but no problem at all!)
Gran Turismo 2: totally perfect
Ridge Racer 4: totally perfect

Einhander: totally perfect
Metal Slug X: totally perfect
Rival Schools Evolution: perfect (just a bit of laggy sound but 100%)

I think that this emulator is the best thing I ever paid for in my entire life. Good work guys!

Games Ive tried that work perfect

Dead or Alive
Marvel Vs Capcom
GT2
Metal Gear Solid
Street Fighter Alpha 3
Tenshu 2
Tekken 3
Tony Hawk Pro Skater 4
Resident Evil 3

If you guys are having sound problems make sure Spu Sync is turned on in the sound settings.

I really hope this emulator is updated to use the analog touch pads for buttons (to compensate for the lack of R2 and L2). Then this would be the best phone and emulator ever.

for above comment try assigning volume up and down button for l2 and r2
good compensation i can think of and its works for me tho

Philosoma crash when push start game.... Just can watch the intro.

I kind of left this thread to die. I got really busy so was not able to do much.

However I have Edited the first post now.
I will also be testing lots of games. Not for just testings sake but I just love the old PS1 games haha
Will update this thread whenever it needs too.

Any problems you have with games. Just post here and i will add it to the first post.