The BS40 is a nose heavy plane, even with a TT46 she is nose heavy. So watch what engine you will use on her.

The 52 4C will give you decent power in my opinion as they will turn a 12x6 at about 10,000 RPM. The Magnum 52 2C is a nice engine. Stick that in with an 11x5 or 11x6 event and she is lovely, you should get about 13,500+ RPMs on 5% nitro. Some even fly her with an 11x7 (around 12,500+ RPM) or a 12x6 (around 12,000 RPMs). I would go with the 52 2C engine, its simple and you can easily back flip the prop to start her ...