Im thinking of getting the SCT tuner from W4M but I had a question. Basically im thinking ahead and want to know will this tuner work on any silverado? by this i mean I have a 2000 Silvearado. If get an 07 or something down the road can I just have them send me an email with a new tune and it would work? I've heard great things about their tunes I'm just not sure if I want to spend another 400 bucks down the road. Also was wondering what kind of mileage gains people got from this tune. Is there anyone else out there that has this tuner for a year around mine(2000). Thanks for any responces!