For hunting purposes, I would value a 4 stroke quad for several reasons. They are quieter, better on fuel, and typically more reliable. They also don't smell like a chainsaw. My FIL has a 2 stroke polaris sportsman 400 (circa 1996), and though it is capable, for reasons listed above, as well as having three drive chains, I would stay away.
As far as your question regarding ccs, it is hard to answer. An old Suzuki king quad 250cc with super low range will out work many larger quads without even low range.
