Quote Originally Posted by OakLeaf View Post
There's definitely a snob element to it, but also the hydration packs that sit high on your back are really unwearable on a road bike - they put too much stress on your back. You'll want one with a waist strap to put the weight of the water onto your hipbones, and just let the shoulder and sternum straps stabilize the position.
This.

I wore my camelbak a grand total of once on a road bike. Not again. It's painful and restricting and really makes a huge difference. A low sitting one I might consider for very long rides. But even my traditional (vertical bladder) bag with a "waist strap" has too much weight up too high. It's never been an issue on the mountain bike or hiking.