I have a OS 91 surpass in the nose. Its a little heavier than the 2 strokes but I use a 5 cell battery pack mounted as far back as possible and a light wooden prop. The CG came out fine. This plane needs a light engine up front. Its not real hard to have it balance proper if you plan ahead. Put 5 flights on it this weekend. Big loops and inverted flight is pretty good - does exactly what you command it to. Not bad in a cross wind either. Really happy with it.