On the Warns, the XT 25 comes with Synthetic Rope which most people find easier to handle than the wire cable, you can retrofit the R/T with this better rope if you want.
If you're serious about plowing snow, you'll need better tires (note my ITP ATR reference for grip), plus even then, you have to take more lighter cuts/passes as the weight/traction just isn't there compared to pickup or Kubota tractor type plowing.
My box came from Cabelas, they have many quad accessories, as well as Rocky Mountain ATV.
I've run both hard and soft sided boxes. this one is perfect, low profile and rugged plus 99% waterproof.
Cabela's: Cabela's Supersize ATV Boxes
Rocky Mountain ATV carries EVERYTHING you may need, and is one of the cheapest tire places around.
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