I think the ACL injury should be a big "no."
Most of the board, very much disliked the way Price played after coming off of his knee injury last season. And very much disliked the way Dunleavy played after coming off of his knee injury the season before.
Well, as someone who has seen far too many players play the "season after the ACL" (thank you, women's basketball) I can tell you, it'll be worse than the two above. And DWest is getting up there in age, so it'll be harder for him to recover from his athletic loss, and possibly the mental aspect of the tear. (No way to really know that. Dun and AJ seemed to be about average in terms of the mental aspect of knee injuries, but I actually question of Rush is STILL dealing with it. I've seen players essentially not be able to play again.)
My point, not worth it. He's not going to be the DWest you are thinking of, at least not this season. In fact, I'd wager that Tyler and Josh would be better, maybe significantly so. And that DWest was probably not worth the money it is going to take to sign him, anyway.
edit: And I don't understand this feeling of "can't have two guys in the post" because, when healthy, the best frontcourt in the league is easily the Lakers. And both Pau and Bynum play in the post.