Ah, I see what you wanna do. Yeah, a premium unit like the Kuuma prolly isn't right for a once-in-a-while burner. Heck, for the lil bit that you'll run it, can you really justify even a Heatmax or an Englander? Put pencil to paper, $1500 (+ how much more $$$ until fully installed) will buy propane for a long time if it's just for deep freeze type weather. This winter has been unusual for sure. Not a good test of "normal" for your stove. I do just the opposite, I run my wood furnace most of the time. I installed a small wood stove in the fireplace this last fall, I fire it up when the weather gets REALLY cold n windy, along with the furnace, rather than run the crud outta the furnace. I run the furnace just like normal, the lil extra from the stove will almost run us out of here. Doesn't take much wood to feed 'er either (1.2 CF stove)
Point is, we had LP logs in the fireplace before, didn't use 'em much, 300 gallon tank lasted 15 years! I wasn't gonna refill the tank (wasn't my tank plus the place I bought LP from quit getting it) and I have wood stacked all over the place, just made sense to install a wood stove. I will run the stove in the spring and fall during those light heat load days too. Alot easier than doing a bunch of small fires in the furnace.