SkiMore,
I would feel better with more truck opposed to less truck. Im running a 2500HD but would rather have a 3500 and i'm sorry i don't. Im thinking of adding a leaf or two to the rear spring pack and not relying on the airbags as much. The airbags still offer good side to side leveling to offset campers that are more heavy on either side. Added spring leafs will offer more support but not officially change the GVWR of the truck. To do that you will a DMV/DOT makeover.
To repeat myself, the rear tires and wheels are the limiting factor and thats what you need to watch. That's why some people swap up to 19.5" wheels/tires,they carry more weight and last longer,commercial grade.
Being that i only use my truck for my camper,for my next truck i would probably buy a LB dually, even to haul my SB 845 at this time. I would use the extra space in the front of the bed to haul equipment for the time being. Having that LB DRW truck,i would be in a better place when i buy a new camper offering me more choices.
SNOW :
I never noticed any problems driving a DRW truck in the snow because the ones i drove were heavy. An empty DRW may tend to float the rear tires in snow. I think you can get used to it and learn to compensate for it,but you will probably notice a difference when riding empty in snow. Four rear tires will be distributing the weight opposed to two, making it float. It just don't know how drastic it is.
I think the DRW/snow thing gets negative attention because the tires on the trucks that people use to professionally plow are srw so they can use a narrow blade. You would have to use a wider plow blade in order to clear a path for the dual rear wheels. Working on homeowner driveways and such, can be a PIA with a DRW and wide blade.
Plowing big roads or open spaces, DRW can be used, but the blade is wider to clear the path for the tires to ride, allowing them to bite.