Osprey atmos 35 pack is brilliant, not only is this one of the most comfortable Adventure racing packs but it is light and robust. The frame allows your back to breathe and keeps the pack in shape, the waist strap is great taking all the weight off the shoulders keeping you fresher longer. It is easy to access all areas and has 2 zips that alow you to open the pack fully, including the water bladder for when you need to refill without disturbing the contents of your pack. There are plenty of pockets to place all your snacks.  This would be in my opinion the best AR pack on the market. The packs come in 35 & 25Lt with small medium and large frames to suit all bodie types.

Disadvantages:

• There are lighter AR packs out there, I prefer a little comfort
• The 35lt is a bit on the large size.