Grate game, bad port.
But onimusha3 also has it's leaks. For first- enemies and combat system- it's very frustrating, when demons doesn't let you to get up when they smashed you on the ground. They can even kill you on the ground without letting you to guard. Second-background music- it's rather boring, monotonic,old fashioned.It doesn't always create appropriate atmosphere (the only place i liked the music in was the underwater temple stages).- Third- background animation- I don't know did ps2 support that, but in the pc version of the game the background is very static.
The game originally was a ps2 game and it was ported to pc. the game has very bad hardware support. even on the lowest gfx settings i lagged sometimes . I played it on 1,9 ghz, fx5200, 512 ram . There was approximately 60 fps (it slowed down in areas containing much lightning and bosses). It's a pitty that capcom doesn't care much of pc players. they didn't even changed the ps2 buttons in the game to pc keyboard (you can get a bit mixed up at times). But I'm happy that capcom at least ported the game to pc's. Maybe they'll be more accurate with RE4 and DMC3. Time will show :)
All in all the game is good. The major problem is technical side of the game, but when you'll get used to it, it will not create problems. Oh, and if you'll play it, I advise you to install the patch ( http://www.fileplanet.com/161488/160000/fileinfo/Onimusha-3-Patch-v1.1.0.0-%5BEuropean%5D ), it solves the low fps problem sometime. You can enter the fullscreen by pressing ALT+ENTER. Remember- the beginning is very boring, but eventually it will get very addictive. Have nice time playing the game :)