There has been a lot of dicussion on this topic. Do a search on the forum and you'll see that most people agree that these are not simple bolt on power ups they seem to be.
IMO they are a waste of time and money but like Lesson said do your research and make your own dession on the matter. I say "no" but that is just me. I am sure several other will chim in with the same opinion but like I said they are all just opinions. There are a few on here that also defend them so.....it boils down to it's your money....how are you going to spend it? I think better pipe or better engine is money better spent.