I replaced my Gregory Forester with the Ozone for my second trek of the John Muir Trail. I added the Granite Gear lid and their lightweight rain cover. With a starting weight of 40, which included 2 liters of water and 7 days of food in a Bearikade bear canister. I was completely comfortable! Carrying the canister in the horizontal was tight and stressed the seams, but switching to a vertical carry solved this. The new Nimbus Ozone does have a hydration sleeve which will make folks happy. Get use to a top loader and you have the perfect pack for the person who wants to carry enough gear to be comfortable in a lightweight comfortable pack.