6:17 a.m. on May 30, 2012 (EDT)
Yeah I understand that the water bottle filters work. They just don't seem to be the most practical or most cost effective option in most circumstances i can think of.
For example the Katadyn Mybottle filter is $59, and the filter element is onl good for 155 liters, and the replacement filter is $49. That is pricey! The Camelbak allclear however is more like the steripen and is good for 10,000 liters and is $99, which is much more cost effective.
I understand if your with a larger group maybe, but besides that the water bottle filters don't really seem to have alot of versatility.
Just because your boiling your water for cooking doesn't mean it doesn't need to be filtered, true boiling will kill all the bad stuff, but it doesn't remove any turbidity or trash from the water if you have a less than stellar source to begin with. A bandanna or other prefilter only does so much. This is one example where I think the water bottle filters fall short, if your having to use it in this manner it would be incredible tedious to use for anything other than drinking directly out of the bottle.
Regarding the Coghlans water filter this one is cheap at $24 but is only good for 400 liters, and the major disadvantage is it only filters to 2 microns, where as most other main stream options filter to at least .2 or .1 microns. This filter has much more of a chance to pass through some bad stuff that is going to make you sick. I would thoroughly understand your potential water sources threats before using this option. the note from Coghlan NOTE: Coghlan's water filter will remove parasites such as Giardia, tapeworm, etc. It will not protect against bacteria or viruses. If you have any reason to suspect such contamination, we recommend treatment of your filtered water with Coghlan's #C7620 Germicidal drinking water tablets.
The OP doesn't have to buy the largest gravity filter setup on the market, but he doesn't have to limit himself to a water bottle filter either if he doesnt want to. There are lots of options out there. Look at your needs, the versatility of products you are concidering, the weight, the cost, and the cost and life of the filter elements before you make a final decision. They all have advantages and disadvantages.
If you really want a water bottle filter though, and you want alot of versatility also, then I would go with the sawyer squeeze. Because, you can screw it directly on to any water bottle with the standard thread pattern(this includes regular disposable water bottles, squirt bottle style gatoraide/poweraide, two liter bottles, soda bottles, platypus etc). Then you could put it on a disposable soda bottle for example and drink to your hearts content, but then when your in camp you could covert it to a gravity filter if you desired. Or pop it off your bottle and attach a bag back to it to rapidly fill several other containers.
Sawyer squeeze $59 good for 1 million gallons, or the Katadyn mybottle $59 good for 155 liters(39 gallons). Which one is more cost effective, versatile? You be the judge.