I have not ridden more than a handful of different makes and models, but my favorite 2 stroke would have to be the LT 250R. I had this as my first quad and it was ridiculous the power it made (ok, it was bored .60 over, ported and polished, head milled .20 and had a Barnett clutch!). And as far as 4 strokes, I have only ridden 1, that would be my '86 230s Quad sport. It is light, easy to throw around, fairly quick, good on fuel, and it even has reverse!