No matter what model you get, DO NOT get the knockoff ones. They suck.
Not all Camelbak knockoffs suck. I recently purchased a knockoff, for a couple of reasons - and I'm very happy with it.
I try to support my USNA classmates in their entrepreneurial endeavors (i.e. I bought the Night Vision Pen), and I have a classmate that took his experiences as an Infantry Officer to develop & build a pretty solid Camelbak competitor. I'm going to be tossing most of my Camelbaks now that I own a
Geigerrig. Some pretty nice features built in, pressurized bladder, can completely remove the bladder and turn it inside out to run through a dishwasher, three different pack sizes, the ability to attach an inline purification system, etc... Plus - it's fun to see Bob with a full beard throwing the pack out of the window of his truck at 60 mph, blowing it up with what is essentially an MRE bomb, etc... (he's got some entertaining YouTube videos). For Camelbaks, my favorite is still the
Stealth, it lays as flat as you can get a Camelbak to lay and was actually comfortable to wear under my flight gear. It's the only one I'm keeping when I do my wholesale clearing out of Camelbaks....
At least you'll continue to be able to buy rubbers at the Buehring exchange. (I still can't figure that one out.)
Dude, it's to keep sand/moisture out of the barrel of your rifle... Seriously...
For flying - CONUS, I fly with a Nav Bag that sits next to my seat. It's got sectionals, approach plates, ANTTP, checklist, and L-charts in it. Maybe a 1:50. In the map case I usually throw my checklist, appropriate sectional and a bottle of water. If it's a long flight, I'll bring a camelbak - if not, I just toss a couple bottles of water from the squadron geedunk in my nav bag/mapcase. FCF hops? FCF checklist, kneeboard, water, and approach plate. Why no sectional? I know where I'm testing and don't need it. But if the shit hits the fan, I need an approach plate.
OCONUS - I flew with a "hit bag", one of my camelbaks with a lot of space, skivvies, socks, wallet, smokes (you can barter with them!), hammock (for a night in the Boeing Hotel), etc... Plus nav bag, and primary camelbak.
CONUS Airshow? Motrin & Water + nav bag. Lots and lots of motrin & water.