Sometimes you get a good deal on used other times not. New engines are not that expensive and is a good way to go. I buy used from a local club member who dabbles in merchandise and he will guarantee his used products. Got a crappy K&B .45 and he let me trade it for a Magnum .45 that screams. These forums go on and on about what is a good engine and what is bad. { Its that ford vs Chevy vs Dodge thing } so manufacture preference is definitely an opinion, In my opinion.