I started the AT with the steripen classic and spent the first 340 miles recommending it as light and convienent but yesterday it stopped working (somethings wrong with the water sensor) so today my girlfriend and I hiked into Erwin without water. I called the company to see what they could get a replacement to me in a timely fashion. I was told that overnight shipping would cost me. They looked it up $40 I was complaining some and they agreed to split shipping with me but I'm thinking that $20 is a good amount of money towards a filter and that while I saw plenty of steripens at the start of the AT I'm not seeing them anymore. Also the outfitters I've been talking to haven't had good things to say about their reliability. So I think it's a bit lame that they weren't tripping over themselves to have me give steripen another chance because as it sits I have to give the review that steripens aren't reliable enough to take into the woods.