SFIV console uses input delay lag, so it's not ideal, but the way SFIV is designed with its ultra-generous buffer window, you should be fine on matches under 100ms lag.

Note: fighting game players prefer rollback style lag to input delay in general, rollback style is only used on two fighters on the consoles (STHDR and Blazblue) and in GGPO (emulator, which has about 10 older fighting games)  STHDR and BB are playable up to about 150-200ms lag.  I'm not entirely sure how the rollback works myself, but it does work better.

Note to Stardock: if you ever make a fighting game, license the GGPO code for the netplay, and keep it P2P.  That's what players prefer.

So, can you play this game with just the keyboard? I dont mean if it's possible to use the keyboard, i know it is, but in reality, do you stand a fighting chance against someone playing with a joypad? I mean, all these fighting games were made for the arcade coin ups, and meant to be played with joypads.

Damn, why did my reply appeared in just blank? I meant to answer that I didnt mean a gamepad like a 360 controller gamepad, but an actual analog stick like those from coin-up arcades.  I suppose this game is better played with those.

Same here!