Trouble is, it depends on whether you winter camp next to the car or haul gear in via backpacking. For the former, this system will be just fine. For the latter, forget it. A single small propane cylinder lasts only three hours; a five-gallon one (the size used with most barbecues) about 35 to 40. But that will also weigh about 30 pounds. The Zodi also needs a car battery to power the blower. So it isn't a hassle-free gadget. I not too sure what you do for extended use in the wilds, as it could get complicated to recharge the battery.
There are other options, though. Coleman's BlackCat Portable Catalytic Heater ($50; www.coleman.com) uses a chemical reaction to generate heat from propane, making it safe for use inside a tent. It puts out plenty of warmth to keep a tent cozy, and runs eight hours off a single propane canister, making it marginally portable for short backpacking trips.
Of course, the heater only heats the tent. It's still going to be cold outside. And that means whining family members. There's not, to my knowledge, a gadget to get around thatB