I took a SteriPEN to Africa for 3 months this summer and the verdict is in: it’s the best water purifier you can carry without a tractor-trailer. It’s basically a UV ray flashlight you submerge into your glass. The water stays cool and it doesn’t change the water, except to kill all the living things in it, viruses included. It is expensive, but pays for itself quickly, as you don’t have to buy bottled water. On my trip, often when I asked a waiter for a glass of tap water, my request would elicit a smile or a laugh. In some cases, they simply would not bring me a glass of water. Most of the time, though, I convinced them — and then, to their amazement, I would take out the SteriPEN, push a button, and stir the water with the glowing purple UV light that always brought stares from other diners. After less than 60 seconds, I would take out the SteriPEN and drink the water, occasionally hearing gasps from other tables. Then I’d mention that UV light is how certain towns and companies now sterilize water.
In the 3 months I used it while abroad, I never got sick and the recommended CR123 batteries lasted all summer. Of course, it doesn’t make Uganda’s water taste any better, and often buying a plastic bottle and tossing it in the car is more convenient, but the SteriPEN will save you if you need it and it will save you money if you use it. For backpacking, it’s what we call a disruptive technology — no other water purifier comes close. I haven’t tried the MIOX, but it seems like a hassle in comparison. You have to make a kind of concentrate that you pour into your water and you need salts for it. I would bet on the SteriPEN because you treat the water 100 percent, there are NO consumables, and there aren’t any follow-up steps, which you might screw up. I have tried pills and filters in the past, but I think the SteriPEN is the best solution in all circumstances. I would take one on an extended wilderness trek with no hesitation. It will become a permanent travel companion.
I bought the lightweight Traveler version (picture above), and my only complaint is that the silver coating disintegrated after a while somehow. It works fine, but now it looks more like a Star Trek prop than it did when I bought it. Since the Traveler and Adventurer models are the same product, just different colors, I would recommend the Adventurer. Quick aside: SteriPEN’s solar charger is way too heavy at this point.