If you do not have a tilt trailer, then a f-350-550, Dodge 3500 or 3500HD Chevy GM 4x4 will be just fine, it just comes down to what brand you like best. I have had my 3500 Chevy 4x4 with the Alison trans for 13 years now and it has been great. It tows my 38 Donzi like it isn't even there.
I had to replace the transfer case recently but other than that, it has been flawless. I am in heavy highway construction and have found that for base HD trucks, Fords are the best. Have had horrible luck with Dodge trucks. The GM trucks by far ride the best, have the most bells and whistles of all three and tow just as much, that is why I will replace my personal dually with another GM truck.

I love my new Sport Chassis. I think the Chevy has more power though. It's just not as refined as the Sport Chassis.