Howdy,
Anyone here had much experience with using these? I've had one for a couple years: well actually, the one I bought last year seemed to not be working well so I exchanged it at REI for another. Now, after further experience with it conking out on me, I think it's just in its nature to fail sometimes. It can really gobble batteries. It may just be that my last batch of betteries were not good enough, but it seems like I'm always making excuses for it failing. The irritating most recent experience I had was that it worked fine with one new set of batteries for 2 people on a 7 day backpack, but then on an 8 day trip for one person, a new set of batteries (and I had no spares: my bad) only lasted 5 days. Luckily I had iodine as backup.
The truth is, it can really be super convenient and light when it's working well. I originally bought it for a backpacking trip in Costa Rica because it is suppose to kill a wider spectrum of bugs than my pump does, but it is also super light.