bzcat is right. You're paying an extra $50-60 for a better sound when accelerating, better looks (chrome or colored), and maybe an extra 2-3 hp increase with the Weapon-R. But i think that extra $50-60 was well spent. The Weapon-R looks awesome in the engine bay, makes an ominous wail when you stomp on the gas, and probably does out power the KKM by a tad.
