They've had some okay ones - Ryan Johnston, Trevor Walker, Andy Lisker, Brock Ratcliff, to name a few. But in their entire history Alex Smith has really been the only standout.
I'd like to give credit to Scott Mitchell for kicking around in the NFL but he sucked on the Lions and he was in my stake for a while he played there. I saw him play church ball and he was below average even compared to other church ball players.