You can't go wrong with either H&S products or the Smarty!
The H&S tuners are going to make your truck blow more smoke if that is your quest. The Smarty is a very clean tuner for the most part.ShaneMSnyder read it again... lol....im gonna "UNBOLT" the dpf and put strait pipe on it with the sims...as far as the Smarty goes ive heard its prolly the best thing for the cummins all around, its kinda a toss up between the Xrt and the Smarty..still want it to smoke like hell and get good fuel mil. and want to be safe as far as the tranny dont have to 7 g's to get the sun coast any help would be nice thanks