Just my opinions: For towing, I want off-idle torque not horsepower at higher RPM. I have a 95 Ram 2500 V10 (488 cubes can't be wrong) with 151K on it. I've been very pleased with this truck and avg 15mpg on the highway to this day. It is equipped with the same (42R ?) auto as comes with the Cummins, so it lopes down the road at low RPM's. My issue truck is a 2005 3/4 ton GMC with the 6.0L Vortec and it downshifts to second gear at 4500 RPM on cruise control constantly, I just cringe when it happens. This is with very little load. When my V10 has seen it's last days, I will opt for the Cummins for outright longevity. I guess it depends on what you want to do with the truck. I'm sure the Hemi would pull a V just great, but at what RPM's and what fuel mileage? My Ram has been very good to me for 12 years and I hope 12 more. One reason I believe is because I hardly work it, even with a trailer in tow. Good luck with what ever you choose. ;)