I think he is really talented. Top 5 CB for sure in this draft, if he is healthy IMHO. However, I had a very different CB list than most.
Daniel Jeremiah rates him VERY highly at #26 on his board and #3 CB overall. I really respect Jeremiah as he has been very solid in the past and actually used to be an area scout in the NFL.
As for the lack of competition thing, great players emerge from small schools all the time. It would bother me more if his tape was not so damn good, however he was rock solid before he was hurt. He might take a little longer to adjust in the NFL, but heck Patrick Peterson looked awful and confused his first 4 games of the NFL. I really think Hayden will be one of 4 #1 CB's in this draft. There are a ton of #2 CB's as well, maybe 10 by my count. Really deep CB class, even with the Slot guys.