The safe pick is Oladipo. I am as certain as I can be that he'll be at least a valuable role player and a high level wing defender.
However, as much as I have some serious reservations about Bennett I think we have to go for him. He simply has too much upside for us not to draft him. Yes he's short, I mean 6'7" in shoes in 2012 & 2011, but he is long & strong. He can score in a variety of ways and his low centre of gravity means he ought to be a physical presence in the paint.
The only other consideration was Len, but a 7ft'er with an ankle stress fracture makes him too much of a risk and that's before you even start to question his toughness.
Voted: Bennett (the only player I really want at 4 is McLemore).