With limited experience they seem fine. I have 2 at my house and although I have not done too much with them yet, no red flags. Then at a sale I have been working at, there are 3 and all are quiet. I would put any age kid on them.
We've had a handful, including the promo bull Chinook who was the only one I put a halter on. He broke in no time, good attitude and never rose a leg. No problems here.