I have a warm and fuzzy spot for PAC springs- you cannot beat them. As for the Jesel rocker system I don't think you would absolutely need them for a hydro-roller 7000 rpm and under app. Atlantic engines entered a 3G Hemi in the 2010 EMC with stock rockers and though it had electrical issues, it was supposed to make somewhere in the 640-650 hp range!!! I think if the v-train is light and durable enough then you can make power elsewhere. J.Rob