I'll admit I didn't read the full thread, but we live in BC as well and do lots of winter camping (on mountains during ski trips) with our older mid-90s Northern Lite.
Over the years I've tried a few options. Currently we use a Dickinson propane fireplace -- which is awesome and uses virtually no electricity (it can be run with or without the fan) and sips propane, and is noise-free. We can ski all day and come back to a toasty camper. We have it mounted at the foot of our 'couch' and it also provides great ambiance inside the rig at night (a flickering fire!)
I should note -- I've also gone to lengths adding lots of rigid insulation, and spray foam where applicable (gaps, the vent lids etc). It makes a big difference. Between the camper and the truck bed I also have 4" of rigid insulation.
When it gets down -15C or lower, the Dickinson takes the edge off but you're still cold. So, this year I added one of the cheap $150 5kw diesel heaters and we love it. I mounted it further back, near the door, so it does a great job of keeping that area and the floor warm.
We've used it on a few trips this winter and it's been great. The biggest problem we've encountered is a bit of condensation on our old single-pane windows and the "problem" that it just plain gets too warm in there! Unless it's -20C we can't run both at the same time.
Last week we were camped on a mountain in a snow storm with 70km winds and one night I found myself standing at the opened rear door in my underwear trying to cool down :)
