Van Persie's attitude has been questioned a few times as well. If Balotelli applies himself correctly and is allowed to the focal point of a team, which I think he will be at Milan and with the national team then he'll have a great career.
I think it's close between the two, Van Persie seemed to be constantly injured at that time and Balotelli has done much more at international level at 22.
Another great bit of local journalism, Pardew doesn't mention anything about Graham not being on our level. He just mentions that he's not on the same level as Remy, which is the type of player we'll be looking for in the summer.