Re: 2-stroke + 2-stroke = 4-stroke!
I really like the way a 2 stroke, China Girl looks but much prefer the sound and power of a 4 stroke. I prefer the ride on a 2 stroke as far as regular bike cranks but prefer the vibes of a 4 smoke.
So, final answer. Love em both. They each have their own qualities and compromises.
All as in-frame. For a rack mount, would go 2 smoker (but building a 4) and for a pusher, with out a doubt would go with a 4 stroke.