My friend has one on an xtra easy 2 and it seems to be ok but he has been tuning it and it looses the tune all the time. I have an Os .46 and it tuned mine in like 3 min and it runs great and never dies his dies all the time. We are brand new to the hobby and have learned everything ourselves with about 25 flights a piece. I like my engine over his but it seems to be preety good.