I have owned a Diamond Dust, a twin engine Diamond Dust and a couple of Mach Racers. All were pretty easy to fly. Deltas can be fast or slow. Diamond Dusts have been flow with everything from a .25 to a .91.

I had piped engines in my 2 Mach Racers and they were fast, but at low throttle, they were very nice. Easy to land. I had one on wheels and one hand launch.