I've been using one of these packs for the past few seasons. I'm a huge fan of the interior divider system and the capacity. Inside I can fit: 7D and 5D Mkii bodies, a 70-200mm 2.8, 24-70mm 2.8, 16mm 2.8 fisheye, a 17-40mm 4, and a flash along with some Pocket Wizard Plus II's (and sometimes more based on the configuration or stacking of lenses).
Carrying a large avy probe can get a little tricky, but a large, square-blade shovel fits in the shovel pocket. Side pockets take on the duty of carrying snacks and I carabiner a water bottle to one of the loops or straps on the front.
The carry system is my favorite feature of this pack. The shoulder straps have the perfect balance of shape, padding, and adjustability and the waistbelt is positioned at just the right height. Burton crushed the fit of the suspension.
Fit reference: 5' 11", 165lb, with medium-width shoulder, torso, and chest.
You pay for all this gear protection and carry-system comfort with a weight penalty though. This bag isn't the lightweight option offered by competitors like F-Stop or Clik Elite, but that doesn't stop me from carrying it on lift days.
Assuming you ride lifts or access the backcountry by sled, this pack is a great choice.