User Review: SteriPEN Classic
Price Paid: group buy $0
I used it for 1 week straight and I was with 10 people we all drank about a gallon a day and the batterys (Energiser-lithium) only died once.
I found it good and fast. We didn't really need it even though we were getting the water from a stream the rangers said they didn't purify it so im not sure how it works in less than spring water but i bring it whenever i go backpacking.
It is nice that if it goes below freezing. I don't have to worry about a filter freezing and cracking and it is lighter than my old filter.