His lack of maturity is going to scare off a lot of teams. That memorabilia incident is going to come up in every interview he does and it's not going to be pretty because they are going to be aggressive. How he answers questions like "why were you willing to put your team and your HC in harms way for a little bit of money when you could just ask your rich daddy for a bigger allowance?"
They will come after him hard for that, you just know they are going to rub his nose in it to see how he responds. I'd also guess that some of the teams will have all theirs of him at strip clubs and the pics from Las Vegas laying on the table to try to unnerve him.
He is going to get grilled to death. If I were his agent I would hire an attorney to cross examine him over and over to get him used to what's going to happen.
As far as his skill set........
To me when you look at a guy like this you can't consider him in the first or second round, maybe the third. It's too big of a risk. Rarely do players like this make any impact at all. Once in awhile you might get one that is decent, or pretty good. But at the price of a first or second rounder it's just not worth it to me. I'd rather have a guy who can be a very good to excellent starter than a boom or bust risk.
Another thing, unlike some of you guys when I watch the highlight clips I am not impressed with his arm. At all. Most of the long passes come while he is running which helps add a lot of velocity and distance to a pass. And a lot of them still float. He has a popgun arm. By itself that's not critical, Montana had the arm strength of a gnat and he didn't get held back by it one bit. At the next level he could turn into an INT machine.
I will never buy into the "he wins, he's a winner" argument like we heard about Tebow and occasionally about other guys. Being a QB on a team that wins a lot in college doesn't mean you can play in the NFL and history shows us that guys like Manziel rarely make an impact.
Frankly I'm not even sure if I'd spend a third rounder on him. I'm sure someone is going to spend a first rounder and regret it though.