PES 5 now allows you to store the results and stats of the games where you play your mates. This can only be done in the memorial mode. Put your pES 5 option file in slot 1 and your opponents in slot 2 (You must now name your option files for this purpose) Over time you get to see whose the best, and the stats will tell you why.
Unfortunately the stats dont seem to be kept outside of the memorial games, which is a shame as I'd hoped for an overall stats package for every game played with that option file. Konami please take note, yes I want to see why I own my friends, but I also want to see how I batter the comp as well.