If the headers and your tuner are that good, offer a money-back guarantee on the sale.
That sort of offer leaves no room for argument and its put up or shut-up.
warmonger
Besides, someone needs to do a proper before and after of just the shm headers with nothing else a factor. I won't buy anybody saying that headers work better with a good tune. Not unless there is intake work done as well. Its just like that stupid MSDS claim that they headers add 25hp when it is really the headers, custom chip and filter.
Why not dyno each part individualy and then all together to prove they work better together or not.
