Finally my glory team gets to face the glory team of the BOA majority! I think I'll go for...
Barca 4 Man U 1
Messi 2, Iniesta 1, Villa 1
Hernandez 1
Saying that, Fergie will probably go really defensive so one goal will win it. But if Barca play to their best (in terms of both their passing game and their pressing game) and United come out to play without being too rough then I reckon 4-1 to Barca. It's conceivable that Barca could struggle if United press the ball really well and play their direct football, but Barca's passing game and pressing should dictate matters in their favour.