i feel like i need my nalgene. my pump hooks directly to it, which it wouldnt on a smaller bottle. i can have coffee out of it no matter how hot it is, i can have a liter of tang with my dinner (rather than using a small cup which i would have to keep filling). its very durable etc. ive tried to get over the idea of "needing" the nalgene but i just dont see it happening. here is a link to my pack:

http://www.ramseyoutdoor.com/productimages/9505f93c-cfb4-43a9-9051-e149fa3cfeaf.jpg

the pocker is the black sloping material you can see along the side. it may be hard to tell but it is very tight elastic so i cant find a nalgene
jake