So far I've seen very few actual back to back dyno's of stock vs. whatever aftermarket system. In fact the only one I've seen is Andy's and he only gained 6whp with a magnaflow. So right now I happen to like the design of the NRP but not the price, I haven't seen one sound clip or dyno of it though. I've heard the others out there but again have never seen dyno's, only heard of them. If you can't post your actual dyno sheet don't bother posting...
Mike