splais:

I have a feeling this question will have a lot of different opinions, but for what it's worth here's mine. I have both a DA50 & a BME50. I don't see why either engine couldn't power a 18-20 pound P-51 Warbird with some authority. I'm not talking 3D either. Your regular scale plane flying, a loop here and there, split S, hammerhead, etc, I see no problems. Both of these engines have a tremendous amount of power & thrust and IMO would be a ideal gas engine for a warbird.

On a lighter side, I don't think you'll be hovering a P-51, it just isn't right!