In the field, I tested the Mr. Heater Buddy catalytic heater. What everyone says is true: it generates a LOT of heat, uses a LOT of propane, and generates moist air. Of all the things I learned in the field tests, perhaps the most important was that my Tepui annex is BIG. Lots of space, which makes it easy to move around and comfortable for three people to lounge in, but VERY hard to keep warm! The catalytic heater was great at warming that large space in hurry. I used a small USB fan to circulate the heat, so it didn't simply rise and heat the ceiling of the annex (the floor of the tent). I was using 1lb tanks, and the heater consumed them at a rate of one per 3 or 4 hours. In the future, I will plan to use a 5lb tank.
This solution is good for morning and evening warm-up sessions, but I didn't really like it as an overnight option. Even with the window flap open, a battery operated CO monitor, a low-oxygen shut-off feature and tip-over shut-off feature, I didn't want to deal with the risks of burns (or worse). Plus, even at the low setting, this heater puts out a LOT of heat. It's a cheap solution (until you add the cost of 1lb tanks), but has some shortcomings.
