I've had a bunch of these trucks.... But they've all been Ford. Had an 08 F350 SRW with V10 gasser, an 07 F450 DRW PSD, an 05 F350 V10 gasser, and now a 2014 F250 6.2L gasser with 4.30 gears.
I usually tow between 9k-15k lbs. It's mostly flat where I drive (S/E Michigan). For towing stability, there's no doubt that the f450 dually was the most stable.
But power-wise, they've all been pretty comprable. I really haven't noticed much of a difference between any of them. My current f250 with the 6.2 V8 gas actually drives and tows very well.
After the excellent performance and dependability I've had with my V10 gas engines, most of my family members have switched their motorhomes to the Ford platform and have been extremely happy with them as well. In fact my parents are on a cross-country trip with their 30 foot motorhome with a V10 and absolutely love it. Extremely reliable and great power.
I was really hesitant to buy a newer Ford with the 6.2 l gas engine, my concerns were that coming from the V10s I would notice a lack of power. I will say that with the 4.3 gearing, I don't notice any difference. At this point I don't see myself ever going back to a diesel. But again, the most I ever tow is 16k. Especially with the additional upfront costs, the additional maintenance costs, and the potential long-term costs of the expensive add-on components that modern diesels have.
What really excites me is the new gas engine Ford is coming out with later this year, the 7.3 l gas. that engine is going to be a beast, and allegedly, according to what I've read so far, they are expecting the fuel economy to be just as good, if not better, than the 6.2 l. From the sounds of it, I don't think most current diesel owners would need a diesel when that engine becomes available.
