Certainly a matter of taste. I preferred Bo, as did my wife. Then again we are late 30s, so it could be a cultural thang. Nothing offensive at all about Carrie - sweet looking and singing. Too me she just seems so cookie-cutter. I think Bo will be a bigger star, but again, that is subjective.
Well, I am 36 and love the kind of rock that Bo does. Grew up listening to the Eagles, Boston, Lynyrd Skynyrd, Aerosmith. Love it!
I agree that Bo will be big. Carrie will do well in the Country genre.