Problem is you have mods. If you get a tech like I know who makes it his life mission to tattle on anyone with mods on their truck, you might not be under warranty. Not saying it will happen every time but it could. You should be aware of that and probably plan on not having a warranty.

The only shops I know of are BTS and JW that don't care and don't car as much respectively. BTS doesn't care what you do. You break it, he fixes it. JW has either the Stage 1 for more than 350 or the Towmaster for less than 350HP. BTS will warranty it for as long as you own the trans and JW is limited to 2 or 3 yrs and 50K miles, IIRC. ATS used to say that unless you get a program that they approve of, you have no warranty. I heard it has changed but who knows.

I prefer to spend the money one time and not have to worry about it again. Is it cheaper in the long run? I think so.