well, i unbelieveably have every fifa....shock horror, excluding the useless special aditions (wc 98, euro 2000 etc)
I also have pes, and Iss pro 2, imo Iss and PES are the best , fifa is good, but Iss beats the hell out of it in all sections barring graphical scoring.
Gameplay is the most realistic of all, if u play football and watch football as most of us do in this forum, if you play both fifa's and Iss/PES u will understand why the games (iss, PEs) are superior.