Its relative. I know people that run a play boat down Numbers at 4000 and people that use creekers on Numbers at 300. Depends on what you are trying to do. Play boats are far more maneuverable, sit lower in the water and are slow. Great for catching every eddy and every wave. Creek boats are good for staying on top of the water, boofing and splatting rocks and punching large holes/running waterfalls. You don't "need" a play boat, but like I said earlier it will make you a better paddler and open the world of playparks and park and play to you.
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