On the contrary I love my pro circuit pipes, and The dyno loves them too. They make more torque and hp than ptr mids, and the dynoport 2 into 1. I literally can have fun going from the sand trails to shooting holes, then climbin hills, and even stay very competitive drag racing. My ported 350 stays neck and neck with my cousins 4 mill 396cc, and I lost by 1/2 length in a drag against a trinity 420cc Stage IV 4mill last weekend. I am a tuner though, so everything on my bike gets tweaked, and even sometimes replaced if it doesn't cut it and do its job right.