What type of diesels do you see on the road all day, every day towing enormous toyhaulers and trailers?......that's right...all of them! They are all good trucks. Every one of the diesels are good engines...Powerstroke, Cummins, Duramax. In my opinion, they have ALL been proven to be reliable and crank out tons of power, it's just a matter of preference.
The dually will give you some added stablity, but if it's gonna be your daily driver, I'd stick w/ the 1 ton SRW. But that's just me.