User Review: SteriPEN Classic
Price Paid: USD 140
Pro: 1. The technology kills EVERYTHING that might be in the water (bacteria, viruses, protozoa...) unlike a lot of other purification systems.
2. No chemicals, no change in taste, no long waits (treating 32 oz of water takes about 90 secs and you can drink it right away).
Con: 1. The lamp is fragile so don't drop it when the plastic cover is off, better yet don't drop it at all.
2. Not really a con, but make sure you get it with the pre-filter, not only will that remove any particles in the water but it also ensures a perfect fit between the steripen and your bottle so you won't spill water or have to perform acrobatics to treat water in a wide-mouth (eg Nalgene) bottle.
Tip: Use it with Ni-MH batteries as you can recharge those and they last a long time (about 50 32-oz treatments).