I've got a decently quick 305, but for the $$, I coulda had a much better 350. That's why I picked one up today.
FWIW, my TPI 305 dyno'd at 223 hp and 277 ft/lbs at the rear wheels on a lean factory tune. But, this is with World Products 58cc heads, a Crane roller cam, roller rockers, and SLP runners. Big money invested in a small motor. However, the heads and intake will get reused on my 350 to save some $$.