Tastes Much Better!
I bought this to replace a camelbak bladder that, despite my best efforts, always tasted like melted plastic. So far I like this Platypus much better. Easy to fill, fits into my backpack and has a clean taste. There is a little bitterness from the first sip if the water has been in the bladder for awhile, but that disappears quickly. Can't speak to the durability just yet, but no leaking thus far. For a water lover, this makes hiking and biking with a bladder much more pleasant.

Simple, tough and versatile
I bought this bladder to fit my Golite Pinnacle (fits perfectly), and I also ended up using it with several smaller packs. On long drives, I sometimes hang it from the back of my seat, so I can have a sip anytime without taking my eyes off the road. I saw several people mentioning that they had problems filling it all the way, I never encountered this. Of course, when pumping water in the backcountry, another person's help is great. Drinking is very easy once you get used to it. The bite valve works as it should, mine never dripped, but it's a shame it doesn't come with a cap by default. The water tastes a bit like plastic only if you forget to blow the water back after drinking. The only downside I can think of is that if you want to refill while on a hike with a full backpack, you practically have to empty your whole bag before you can take it out and put it back full.

I like this one the best.
This model is simple. I know they make zipper topped models but I have trouble closing them. (I guess I have weak thumbs OR I don't know what I am doing) AND then I don't trust that the zipper will stay closed in my backpack....even though they say it will..... So I like a screw on and off cap.

Platypus bottles are terrific. Low weight, excellent quality
I have used Platypus bottles for many years. They are very light weight, can be rolled up into small size and work really good. No problem keeping them clean and water tastes great out of them.

A quality hydration system
The Platypus Hoser 3 liter hydration system only weighs 3 3/4 ounces when empty. It is lighter than other hydration systems and every ounce you can save in your backpack makes it easier on your body. There is no leakage from where the the hose threads to the bag. My wife has the Platypus Hoser 2 liter, and we are very satisfied with both products and would recomend them to a friend.