I can tell u that there's a slight difference between each region as sadly I live in the region that receives it last. I don't bother with modchips so I usually play with a friend who has 1 b4 the International version finally comes out.
The time I played all 3 was PES3, WE7, and WE7I (my copy). WE7 was the fastest, PES3 was slightly slower, and WE7I was somewhere in between. Since then I would play PES occassionally until International comes out which is when I would do all the editing and play leagues and master league.
And transfers. They add in some summer tranfsers in the International. Like in PES5 Owen would not be in Newcastle by default, whereas in WE9I he is.
I think the pace has to do with how each region prefers to play the game.