P.S. Flying a 50cc size gasser is waaaay more fun than flying a 6.25 pound plane with a Saito 100
It depends on what floats your boat....
I've seen 3 folks flying Wildhares at my previous field with 50cc DA's, and it looked pretty boring to me.
Given a Saito is 1.2 lbs and puts out 12.5lbs of static thrust, we should be expecting that a 3.1lb motor put out 32+lbs of thrust if they were linear. I bet we see it within 5 years....probably within 2.