Actors are all wrong!
So let me get this straight,
Jay:
UK Version - Cocky, *beep* guy who is pressured into enlarging his ego and is obsessed with sex
US Version - Fat, Jonah Hill lookalike, looks like he'll have zero self-esteem
Will:
UK Version - Sweet but dorky over thinker, worries about exams and further education, very smart, always feels like he should of lost his virginity, but feels like the least worried out the 4 about it
US Version - Goddamn *beep* pretty boy who we will have to buy into being a loser and not loosing his virginity.
Simon:
UK Version - The straight guy of the gang, love struck by a crush, desperate to loose virginity, always ends up being the one who has to suffer the most
US Version - Probably more of the same
Neil (and this is the big one that makes zero sense):
UK Version - Stupid, always getting buying stuff Jay says, gullible, never quite understands anything to the full extent and is happy with anything
US Version - Some emo rocker skater person
Now I haven't seen them act, but it doesn't look like these people would either be hanging out with each other, or (with the exception of not-Jonah Hill up there) be the "Inbetweeners" of the year.