I have a bit of an obsession with hydration paks and bladders. My latest purchase was a Nalgene Draft 3.0L that I got on clearance from Nashbar. I'd read a lot about them, and the consensus was that the pack was great, but the bladder has a tendency to leak. Well, I've got another 3L bladder that is nigh-on indestructable, so I figured I'd just replace the stock one with my current bladder if it started leaking. Well, it did. After 2 rides.
I thought, that's just silly. Nalgene doesn't put out crappy products. So I got in touch with customer service, and learned that the handle you hold onto when you're filling the bladder (it's right next to the fill hole) actually unscrews, and you can remove it. When it's on, though, it has to be screwed underneath some tabs, or else it doesn't seal properly. I'm convinced that this is the problem most people had with their bladders, they just never took the time to get an answer from Nalgene.
It works perfectly, the pack is well-insulated to keep my water cool, and it's really adjustable. It has plenty of room for goodies, and was cheap. I'd definitely recommend it to anyone looking for a sleek hydration pack. There are days when hauling around your M.U.L.E. is just silly.