Brunton Brewfire Review
I bought one of these new. Like many people have found, it didn't work. Being an engineer, I took it apart and discovered that one of the screws holding the tilt switch was gone, letting the switch pivot down. I replaced the screw and put it back together. After that I only used it a few times but it worked fine, although the brewing time is a lot closer to 20 minutes than the advertised 12.
All of my camping gear was stolen a few months ago so I've been replacing things, including a new Brewfire. The new one didn't work either, so of course I opened it up. I found that the tilt switch on this one had fallen apart. I was able to glue it back together and now it works as well as the last one.
My conclusion is that it's a great idea, poorly executed. Brunton needs to look seriously at their quality program and procedures. Or, maybe someone in the US will produce one that actually works out of the box.