No hard feelings if he leaves. He is an awesome talent with a fair amount to prove still, and BYU is the place to prove it.
A Ty Detmer offense will be good for him to showcase any improved passing ability he has, will be his best chance to stay healthy (scheme-wise), and will be great for his NFL stock if he is still entertaining early-round draft dreams.
IMHO, more risks and unknowns at other schools, including UVA.