The First Need water purifier was an easy choice for me to make. After two consecutive years of backpacking and elk hunting with a "seasoned" backpacker friend (into wilderness areas) who carried his everywhere, I saw first hand the value of a dependable water filter. Not only is it a true purifier (we drank purified lake water), but it also is durable and Nalgene bottles screw right on it. I was fortunate to see the First Need purifier operate in the field and I anticipate years of service from mine. Thanks for carrying this high quality product at a great price.