I added a PCIII to my 07 Ultra. It is stock otherwise. The exhaust crossover does not glow brightly at night any more. I think it is a little quicker, but have no quantitative data to back it up. MPG on the 1st tank dropped from the 36 or so I was getting to 32. I beleive that was due to numerous runs up to 100mph trying to determine if it was faster. MPG has returned on subsequent tanks. KHILL