Your're right about being expensive and unknown quality but the saying "you get what you pay for" definitely is true with bike engine kits. Seems most of you guys go for the 2 stroke China jobs. They are definitely the cheapest, and not only in price. From what I've read on the forums, they require way too much TLC and upkeep. That's why I'd rather have a 4 stroke. Yes, as I said, the "Bridgestone" engine sounds like a real cheap knockoff and quality is completely unknown. But engines like Robin Subaru, Tanaka and Honda are very well known for quality. If these engines were available on every kit out there, at least as an option, we'd be better off. But these engines just don't look as cool to some. Staton makes high quality kits but most of his are way too offset to one side on the rack mounts for my taste and he doesn't do frame mounts and he's expensive, but again, you always get what you pay for.