Fifa all the way there really is no competition in PES anymore. I was a PES fan for years but you want to talk about a sports game that never changes really? Madden has nothing on PES.
Xblaz23? Turn EA game up? I think you have that backwards because FIFA killed PES for the last couple years and its not just my opinion, reviews, boards, everywhere you look its Fifa all the way with only the most die hard Seabass fans claiming PES is close. PES has had an unforgivable horrid time jumping to next gen and at its best its pretty broken.
Dont get me wrong PES was a fantastic game around the PS1 and PS2 era but Fifa has made some crazy strides in the last few years.
Lives Seasons, Full 10 on 10 footie (that actually works mind you) 95% of all the leagues, clubs, kits etc, 2nd to none commentary(in my opinion the best commentary in any sports video game) I can go on and on.
Fifa gameplay is also on par or slightly ahead of PES now which was the biggest concern with Fifa in the first place. Now everything I see on the pitch is in the game so it no contest.