We've been through that experiment, he is not a 5/8 or a half. He is a servicable subsititute. He may make a 13 with an off season and an attitude adjustment to his role in defence, dirty hit ups and the kick chase. AD is a good clubman, much like Twal and Seyfarth (but with more upside than the latter). If we are serious about having a crack at a premiership AD is depth (unless he makes a transformation to 13 over the off season).
From what I have seen of him at 13 (which admittedly isn't a lot) he does not share the middles workload well enough, he does not participate willingly in the kick chase (where he should be one of the leaders) and he id lazy in defence (sure he makes his tackles, but does not apply good inside pressure and for the life of him would not make an effort to chase anyone down unless if he could leave it to someone else).
Even yesterday, where he had a great game with ball in hand and made some good one on one defensive reads, the effort areas in supporting his team mates was low. He drives me insane - he has talent and skills but is so bloody lazy in aspects of his game.
If Benji can get himplaying to his potential as opposed to what he is comfortable with - he can be a real asset. I guess the ball is in his court.