I've worked on Southwind heaters in light twin airplanes, and there are a few things you should look at. Basically if you plan on actually using it as a heater, you need to do a leakdown test on the combustion can. The outside may be shiny but if your burner can has holes in it, you are going to be breathing a lot of carbon monoxide when its on. I don't know all whats included in the one you are looking at, but the ones I'm familiar with have an associated fuel pump and fan. Also you might want to check on the price and availability of the igniter (a glorified sparkplug).
