Not everyone should play with things that go BOOM. The easy part is just don't buy it. Don't whine about the guy selling it.
Well, Cliff,
Maybe so, but most people would have no idea that it has the potential to be as grossly unsafe as it is. Perhaps at the very least my blog post will serve to educate.
At -20 deg F, this solution may work fine.
100% propane in a backpacking canister actually would be fairly safe at -20F. At -20F, 100% propane would be at about 11.5 psig. Backpacking canisters should be able contain at least 100 psig (although you're starting to push it there). You'd have to be really danged careful you didn't forget and bring it in the nice warm house after your trip.
But I still wouldn't use this el cheapo rig with aquarium tubing to try to transfer propane.
If you get one, let us know how it goes.
HJ