For me anyone (fifa or pes) has a quality simulation of the game for this Gen. I used to be a Fifa player in the 90s but in the 2000-2007 period i prefer PES o WE.
I have played both games from ISS on SNES or FIFA 94 in PC, i have played both in PC and Consoles (NES, SNES, GAMECUBE, PS1, PS2, XBOX, XBOX360, etc...) I will not convince anyone about what is best for me that's a matter of personal taste..but here what I think now:
Fifa is a good game, the quality of the animation are awesome ,are worthy of this generation, the keepers are from another planet. Today, for fifa the main focus is to deliver an experience that be closest to a live TV Transmision, and they did that very well. All the elements in FIFA are created to represent TV and when you see it in youtube ( Fifa 9 and 10) you see what i mean. They make a engine focused in that, and that engine do the job very well.
The gameplay in FIFA is good to, but it is non-realistic to me, because all the players do the same things... I take ronaldo and do every kind of tricks, an after i take Puyol and he do the same tricks, but in slow motion; The tricks havent a effect in the play, are simply aesthetic. Every player feel like the same... The teams have the same issue, every team play in the same way with very small changes, every team felt like 70s Brazil. Accurate passes, perfects throws balls, excellent crosses, every player run forward searching the space beetween the defence. These things are simply NON REAL at all. Even a monkey can play FIFA in a good manner and maybe win some matches in front of the best player.
In the other hand we have PES... oh my good Lord...PES...IMO konami need a new engine and a new producer...someone angry for glory. A youngest "seabass". Simply konami take 3 years to take PES into this Gen... and is too much time for the consumers.
PES 2010 seems to be a good game aswell, but with bad things too. The gameplay, In Pes 2009 we se the individualism, and in the 2010 demo, we see the pass pass pass game, where is the balance?... I dont see it. The keepers are simply a shit, They are like some kind of moving wall in the goal... All animations are as an accelerated, badly done work.
In my summary... PES have the induvidualism in the players and in the teams, and the graphics... and FIFA have the animations, the keepers, the atmosphere, the licenses and the engine.
If we can take the gameplay from PES5-6 and put into the engine of FIFA 09, then we will be talking about what i imagine for the simulation in this gen.
Today for me, Fifa its a visual fantasy, and Pes is like football in ugly, realy ugly clothes.
PD: I preffer football in ugly clothes, but some times i would like a good looking girl, with big silicon breast, too.
sorry for my english...