I have used the DaKine products for 10 years easy, first for snowboarding and now with the transition to Sleds. I don't know how much crap that you bring with ya but for me their Heli Pro pack, has been standard issue for me.
www.dakine.com/snowboard/packs/snow/
Whatever you go with, an internal hydration system( camelback ) is a must, it saves the space of not having to pack a bottle as well the bladder for it can conform to whatever shape that space provides.
As for the durability, the pack that I'm using now, I've used for three years, for two of those working as a backcountry sled guide in Whistler riding 5 to 6 days a week!
Oh and one other thing, DaKine gives a Lifetime Warranty!! Which they will exchange no questions asked( as long as ya kept the receipt ).