I bought PES and FIFA last year. They both have their pros and cons.
PES just looks like soccer. I'll watch some goals 5 or 6 times just because it looks like something I'd see in a real game. However, I do hate how the players run. And the whole master league thing, ugh. Just absolutely kills it for me.
FIFA plays fun, but a lot of the goals seem the same to me. However, with the actual leagues/league setups, FIFA will always win for me.
Guess I can't have my cake and eat it too.