I have the Aeroworks 35CC Extra 300 , the sister plane, there is a huge thread on these planes in the Giants and Aeroworks forum. I have a Brillelli 46CC in mine, excellent vertical and power. The Brillelli 46CC is what Aeroworks used originally when designing the plane, so a 50CC would not be too much. This is an excellent plane btw, excellent construction and flight performance for IMAC and 3D.