The water bottle based ones are great for EDC. If you're gonna carry a bottle may as well be one that can treat nasties. If you EDC a hydration bladder consider a gravity filter like the Platypus/MSR one. The unit with tubing and second "dirty" bladder is about the size of a 32 oz bottle. This will give you lots and lots of water from virtually any source... If you are worried about chemical contamination add a carbon filter to it. I also carry a sheet of spinnaker cloth that can serve as a tarp for staying dry and collecting rainwater, or for doing the condensate thing with too... Finally I have an MSR WaterWorks thats still going strong... Lots of options depending on where I'm going to be (region).
for edc I keep a small straw type filter because Its an item that is good to have but the chance that I will need it is very slim so I went for the smallest and lightest one I could find.
I keep a water filtration/treatment kit in my EDC bag in an Otterbox 3000. It includes an AquaPouch and an AquaPouch Plus (both completely flat one liter containers, the Plus has a flat folding funnel that fits conical coffee filters for removal of fairly large particles), MicroPur tablets, a Camelbak folding water bag, a Frontier Aquamira Pro filter, and some plastic tubing. I also carry 2 40oz. stainless water bottles. My bag is an Osprey Kestrel 32, so it has plenty of room, but it does not go everywhere I go - the grocery store for instance. As a civil-sanitary engineer for nearly 40 years, I'm very serious about water treatment.
As am I. I have a Whole House Carbon water filter at my Main Supply. I EDC over a gallon a day of great water
Yes, I keep one of the McNett straws in my kit as well. I think I'd have to be pretty desperate to use if. I haven't actually seen a Life Straw, though the spec's sound good. But I can generally get the McNett straw and the Aquamira filter for about the same price as one Life Straw.
My GHB in my trunk has water packets, and a katadyn water filter. My fatboy just has purification tablets.
