Aquamira Water Purifier Tablets
Price Paid: $12
Way back when I hiked in the White Mountains I didn't treat the water at all. These days I wouldn't think of not treating and I haven't felt like putting out the $75+ dollars for a water filter.
I always carry these tablets, even on day hikes. They weigh nothing and are an easy safety net in case I get stranded. On backpacks nowadays I am always with a larger group so, should I not be able to wait for the four hours, I could always borrow someone's filter. Haven't had to do that yet.
I don't detect any taste. There is a slight chlorine odor, but it is hardly noticable. I usually bring one or two extra water bottles in case it looks like I will run out or there will not be water at the campsite. Then I fill up somewhere on the trail and by the time I get to camp or dinner is over, the water is OK to drink.
Price Paid: $14
Bottom line -- don't leave home without it.
I've seen and experienced all sorts of troubles with so called bomb-proof water filters and the end result was usually one of two things: you're at the mercy of some rancid tasting iodine tabs you can pick up at Walmart for the spare change in your pocket, or you're forced to head home early.
I bought a 24 pack to carry as a backup I actually wouldn't mind using if faced with filter troubles. They pack down small, don't hardly weigh a thing, and the package is surprisingly thin...there is no good reason you can say they're an inconvenience to you.
The time it takes to be fully effective is the reason I won't give it a perfect score. It will kill all bacteria and parasites within 30 minutes, but up to 4 hours(!) is the manufacturer's recommended period to ensure that giardia, cryptosporidium and other viruses are dealt with.
Iodine on the other hand has one major limitation... it is ineffective against crypto. Aquamira in a sense has become my insurance policy and has its regular place in my emergency and first aid kit.
Most guys who use a chlorine dioxide based treatment will only wait the first 30 minutes before deeming the water safe. All of what makes untreated backcountry water questionable is killed off in that time, whereas the full treatment period is required for third world type of places.
Pay as much attention as you do to keeping your water safe towards keeping your hands clean and sanitized and digestive tract illnesses are likely something you'll ever gain firsthand knowledge of.