I just put this plane together as my 1st giant scale. I am running a DA-50 and love it! Tons of reliable power, and if you get into trouble practicing 3d it will yank you right out.. I was in your same shoes not too long ago about the engine selection for this plane. DA-50 is too much for this plane, don't waste your money on a 50cc ect... I figured eventually I'm going to step up to a larger 30% airframe and need a 50cc and thats why I went with the DA. The H9 260 flies great with this setup for me, and I could not believe how slow the plane comes in for landing. With a little breeze you could almost keep up with it at a fast walking pace. Anyway thats what I went with and am very pleased.
Dave