Bests & Worsts Reviews from Amazon

I received this warmer along with a Zippo lighter as a birthday gift. And what a gift they are! I've never heard of/seen these before and wish I'd come across them years ago. I live in Florida, so that might explain it. My body struggles to stay warm often, so this warmer is quite a blessing. It just so happened that I was out of town this weekend, first real cold front of the year, my friends decided to take me to a restaurant with outdoor seating, and I hadn't quite packed warm enough clothing. Zippo hand warmer to the rescue! I only put 6 hrs' worth of Zippo fluid into it and it ended up going for 12 hours. Even though I only had one, it kept me comfortably warm. A few observations: 1) Take your time in filling it up, as it's easy to fill it too fast and have it spill. Wipe off the extra and wait a minute for the excess to evaporate. 2) The instructions say you're supposed to use 2x the fuel the first time you use the unit. See #1 -- I tried putting fuel in too fast and ended up spilling a bit, which ignited on me when I went to warm the burner. Not a big deal -- just blow it out. Still, it was a bit exciting for a few seconds. 3) The warmer put off a noticeable burning charcoal lighter-fluid smell on the first burn. Subsequent burns haven't produced this. 4) It's best to let the unit get up to temperature by leaving it UPRIGHT outside of the pouch for a good 5-10 minutes until it gets almost too hot to touch, then put it in the pouch. It'll stay nice & warm from that point forward. I've occasionally had it lit, then set it down flat only to find that it had extinguished itself. I finally figured out that laying it sideways was sending liquid into the catalyst, quenching it. The catalyst works on vapor, not liquid. 5) After refueling, wait at least a minute after attaching the burner before trying to light it. The catalyst works by oxidizing the vapors from the fuel. Giving the vapors time to permeate the burner will make lighting much easier and faster. 6) In the initial stages (after filling, after lighting), I find it helps to prop the burner upright to help get the fuel vapors rising into the catalyst. 7) If the burner and/or cover aren't fitting tightly, you can squeeze the edges closer together with your hands/fingers. I've not had a problem with the burner popping off like other reviewers had, but I did tighten mine up to be on the safe side. I'm planning on buying a second unit, so I can have one in each pocket. *** Update 11/19/2013 *** Okay, so I've since bought a second one and have had the chance to use these about 10 times now. They definitely get easier to light after the first 1-2 times. I'm still getting ~12 hrs out of "6 hours" worth of fuel according to the little Zippo fuel filler cup. I've also tossed these in the bed a few times as well on the cooler nights when I didn't feel like turning the central heat on. I also notice that there's virtually no smell from them when they're going unless you have them right up near your face. I'm really surprised at just how well these work at keeping me warm, and I do get chilled very easily. In times when I'd normally need a jacket, these keep me plenty comfortable without. I also have to say that they get plenty warm. I'm not sure how/why people aren't getting plenty of heat out of them -- I get plenty, enough that the warmer can't be held comfortably in my hand without being inside the felt pouch.