It really depends on what year you are considering. I would buy something 2006 or newer only because the V-10 and 8.1 had the most HP and better transmission by then. If all things were equal I would chose the 8.1 over the V-10 because of the Allision transmission. Also some of the older V-10's were very noisy because of the higher rpms required to make the 362 HP. In the newer ones more gears were added and dog houses seem better insulated and the higher RPMs were not as objectionable, but I am used to an old 454 that makes max torque at much lower rpms. You can't go wrong with either after 2006. Older than that I would get the 8.1.