I hate to disagree with you Tom...
Why the hell not?
I would guess that it would be 90% or higher green 2 strokes.
That's awesome. 2 strokes are so simple and so efficient at what they do, it would be a shame to ditch the technology without good reason.
It's tough to imagine a 4 stroke putting out 400 hp at 10000+ RPM with an engine that weighs about 175 lbs and an entire drive train that weighs about 350 lbs. It just ain't going to happen any time soon.