I needed a pack to carry a few more items than my shuttle pack would allow so i picked up the Drafter. The main pocket is big enough that i can put my collapsible Platypus "platy bottle" in their for those long rides when you're gonna need extra water and it also has inside organization pockets for tools, hand pump, energy bars, keys, etc. The hydration bladder made by Nalgene is my favorite bladder yet, i will use this bladder for hiking in larger packs too. It's way easier to open than the camel back bladders (i once had to use pliers cause my old camel back one was so stuck on there!) and the detachable tube is a really nice touch for refilling. The lock mechanism on the bite valve is nice and easy to use too. Flip it straight to lock, turn it 90 degrees to open.
I also like the helmet pouch, it's nice to have place for the helmet vs rattling around in the back of the car, and i guess there are some people who would take it off for climbing (not me, but whatever) so it would be nice for that. I put my arm guards in the helmet pouch last night for the climbing part of our ride and was able to easily pull them out the top without removing the pack from my back. I think shin guards would be too big to hold in there however and would end up hitting the back of your head if they even stayed in.
I haven't used my shuttle pack since i got the drafter. It's been perfect for all my rides (usually a bunch of climbing with a nice downhill payoff is my style) but sometimes get suckered into longer cross country rides and will most likely use it for some lift served as well.
Oh yeah, and it looks way cooler than any camelback style!