an updated Radius, same rocker with a touch more curve through the tail, same single concave, squash tail has more of a pulled in tail block, slightly wider through the chest then Radius, more rounder user friendly rails than the Radius.
The Radius Prime has a wider wave range than the Radius, good surfers can ride it in smaller waves and still lights up when the waves are good.
JJF just had some in NZ and was loving them.