Alves is a quality player. Great signing.
Hleb? Arsenal are letting him move, and when Wenger lets a player move he is rarely proven to be wrong (only Van Bronckhorst has gone on to better things from Arsenal in recent years). Hleb is like Flamini - the players around him in the Arsenal side have made him look better than he is.
Benzema - absolute quality in his game against us. Possibly too early for him to be making such a big move, but definite potential.
Pique - couldnt force his way into the Man U starting lineup past the **cough** "best centre half partnership in the World" **cough** (copywright Alan Hansen and Mark the human goat Lawrenson).