JBA engines might be a good deal, and may be very good engines. However just because they look like OS engines does not mean they are OS engines.

I bought a plane that looked like another, more expensive plane. Almost identical. No matter how you spin it, it is not the same plane. I can say that the extra money goes somewhere, like toward high quality parts and first class service and support.

I have found every OS I've owned to be worth the extra price.