Up until the last 2 games, I thought Quinn was clearly ahead of Arch in his ability to diagnose coverage's pre-snap, and to get to his 2nd and 3rd reads on passing plays. Arch, on the other hand, had the advantage of using his legs, and throwing the deep ball. So it seemed to me Quinn had a better overall grasp of the offense and how to get the ball to the correct target and to move the ball down the field, where as Arch was the better athlete and could make some things happen because of his athleticism, but might be more inconsistent due to lack of experience.
But, after the last 2 games, it looks like Quinn has regressed mentally and lost confidence. He is hesitant and playing to not make mistakes, which of course is leading to more mistakes. It didn't really matter against OU, but Georgia is a different animal. Georgia sped him up and really got into his head. If he can't get his confidence back and his head straight during the Vanderbilt game, it needs to be Arch time. I wouldn't give up on Quinn yet, but he needs to be on a short leash.