If you like them then who cares what others say...
There are quite a few engines I would put on a rung below the K&B - Two of the best kept secrets in RC is the Twist-61 which sits in a 46 sized case- and the K&B Screamin' 48... Very powerful, quiet and easy to tune- (A bit heavy tho)
Jett and Nelson speak for themselves--- I try to buy american with most things but with RC I enjoy trying the cross-section of engines-