But remember, a 2500 diesel (maybe gasser too, idk if GM uses the same axle for both) is the same truck as a 3500 dually minus the extra springs, hips and 2 tires.
Translation: aside from the inherent stability of a dually, mechanically, the OE springs and whatever wheels and tires are on it are the ONLY physical differences.
Both of which are easily and economically up grade able.
Unless you're stuck on stickers still.
Note I'm still not condoning a first timer to hook a 9ton fiver and floor it up the mountain pass. Driver capability/comfort plays at least as big a part in the equation as vehicle capability.