Playing QB isn't about speed. It has been said time and time again, but Peyton manning is not fast, at all, and was still the least sacked QB in the NFL this year. Having said that, its all about the internal clock and whether a QB can make the proper moves in the pocket to avoid the rush.
Bray showed all throughout his senior season that he could do that. Being here for spring workouts and practice gives him a HUGE advantage over Nance. With his frame he has plenty of room to add the weight necessary to withstand the hits. If he doesn't start for at least 3 years while here, I will consider it a bit of a disappointment.