The .40LA isn't a terrible engine, it should be as powerful as any other 40 sized engine. It's just a little cheaper then all other 40 sized engines becasue OS uses cheaper parts on it. You'll notice that the backplate is plastic, so if you were to crash, there is a good chance it would break and you would get into ordering replacement parts. There are serval cutbacks similar to this on the engine, but fly perfect every time, and you'll never have a problem.