Nitro Planes is a distributor, CMP is a manufacturer. Nitro planes sells some CMP, some clones. Indeed weight is always a factor for warbirds, but with this plane you need some nose weight anyway. A 1.20 or 1.25 seems just about right, and is not overpowered. I would think a .90 Four stroke on this plane would be weak. Yes, it would fly scale, but extra power can help you out of many jams that would have the plane crash with scale power. A .90 two stroke would have enough power, and has been used in magazine reviews that I have read when used with a bunch of lead in the nose, but the larger four stroke is the way to go.