Extremely comfortable. I just swapped out my old pack (4800ci and 6lb 5oz) to the Ozone (3800ci and 3lb). I couldn't believe how much easier and more comfortable my trip was compared with using the bulky Jack Wolfskin. All my gear fit perfectly for my solo overnighter. With the extension fabric on top I'm sure I could fit enough food/gear to pull off a five-day trip. This pack's suspension made my 24lb pack feel like 15lbs.

First of all, the Nimbus Ozone is much more than a "weekend" pack - I used one for the northern 1000 miles of the AT (Port Clinton to Katahdin) after getting tired of sore shoulders with the GoLite Trek I started with. 3800 cubes is enough for gear plus 5 days of food and a 2-liter Platypus. For me that's 22 lb + 12 lb + 4 lb = 38 lb. (Granite Gear's Ultralight packs of comparable size are rated for 30 lb loads.) Compared to other heavier packs of similar size and 40 lb weight rating, the Ozone's 3 lb pack weight is a tradeoff I'll gladly make, because every ounce counts when you're on a long trek. You can go farther, be less tired, and reduce the likelihood of chronic foot and knee injuries if you reduce overall pack weight, and the pack itself weighs more than any item within it (unless you have a heavy tent). With the Nimbus, you have to forego features like a detachable fanny pack top, access zippers, and assorted compartments, but not durability - my original Nimbus Ozone is still holding up well after 1800 miles. It's comfortable even with a full load of food, and convenient enough for my taste.

No frills, easy packing and rugged. This has been through 5 countries and many trips on the trail and it has handled everything I have thrown at it. If you're a minimalist like me it will handle anything you can throw at it.

It's just a straightforward bag, with tons of room for anyone trying to travel a bit lighter. But it's put together beautifully, with all kinds of ways to make it fit just right for each individual. Very comfortable, even with a full (40 lb.) load. Only complaint is a lack of any pockets to put stuff you might want on the trail, but you can add one or more as an accessory. While it's quite light for its size, it is very strong and able to stand up to granite, etc., unlike the superlightweight options, which use less rugged material. Choose this pack for years of great trips.

This is a terrific pack on the trail, as comfortable as promised, light and well hung. It could be improved with front pockets on the hip-belt for easy access, as some bags have, and with a hydration sleeve -- but the side and back outsides can be adapted without much difficulty. The pack comes with different size hip belts and shoulder straps, that BackcountryStore does not specify on the site; if you are large, make sure to get them; there are lots of adjustments possible for a terrific fit. Naively I committed the pack to the airlines, and that was a mistake -- ship it inside a duffle or some other protective cover.

I bought this pack so I could shave a pound or so off my current pack. This meant dropping some volume (down from 4500). Amazingly I find this pack to hold pretty much all the usual climbing gear with ease. Ice axe, crampons, rope, etc. There is room for the tent and the rest of it too. I credit that to the well designed cinch straps on the outside of the pack and the generous extension collar at the top of the pack. You can overstuff this pack easily and still maintain a stable load.

The fit: I'm 5'1" and the regular size pack fits me very well. Carrying 32 pounds was a breeze and felt light. The pack shipped without any options on the shoulder and waist straps, but a quick phone call to Granite gear took care of that. They shipped me the correct sizes UPS second day air so I could go on my trip. That is customer service!

Ease of use: Easy. Top loading so harder to get to stuff but that is a given for the lightweight design. I have to gripe that they don't allow for a hydration bladder. To keep it lightweight they probably nixed the hydration sleeve since not everyone uses a bladder. However it would have been nice to have a grommet or something to allow the hydration tubing to exit. Plus a lightweight clip or something on the inside of the pack frame to hang a bladder from would be nice too.

That said I love this pack and would recommend it highly. I would buy it again, epsecially if they made slight changes to accomodate hydration bladder.

Replaced my Gregory Shasta with this pack as the core of my new lighter-weight setup. This pack is amazingly comfortable and swallows much more stuff than you'd think. I had plenty for a four-day excursion and even brought my bulky Nikon D70 camera and tripod along (just strapped it to the outside of the pack). Comfort even with 30 pounds is outstanding. I sweat a lot, but the meshy fabric breathes well and dries quickly. The pack has also proven quite durable in the two season's I've owned it.
Nitpicks: I wish the pack liner was a lighter color to make it easier to spot things inside, and the external stretchy slash pockets are hard to access when the pack is stuffed full. It would be nice if you could remove the hydration bladder without having to dig down inside the pack itself, also. Overall, though, its a simple, dependable, and versatile pack that's quite literally a pleasure to wear.

I gave up backpacking for a few years because I could not find a pack that did not hurt my back. Then I found the Ozone, with its fit system and no back pain! I have used the Ozone three times for a week each time and it has to be the best pack, it carried the load very comfortably (23 to 38lb) my friend carried the Ozone for 30 minuets and purchased one and is very happy also. Back problems or not this is a great pack; I would recommend this pack to anyone. Thanks Granite Gear.

Very light for the level of comfort and the load control. Very few bells and whistles, so order the top pouch. Also, beware when ordering by mail. Granite gear has many different sizes of hip belts and shoulder harnesses that are not available through this site. One size does not fit all!

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.

I thru-hiked the PCT with this pack and was quite impressed. I needed something that was lightweight, yet able to hold moderately heavy loads for short stretches, and the ozone fit the bill nicely. As advertised, it comfortably held between 30 and 40 pounds without putting too much strain on your hips or shoulders. The material is lightweight, yet really durable so long as you don't toss it around like a bowling ball. My only gripe is that the screw that holds the right strap onto the frame tends to loosen up and come out if I don't check it from time to time. All in all, a great pack that I still use, even after putting 2,600+ miles on it.

Nice work Granite Gear. The pack fits soooooooooo good. It is adjustible to get the perfect fit, just hugs your back, supports 35 lbs perfectly. For me I could use a few more pockets and such for organization, but I'll make do by ordering GG hip belt pockets, I already own "the lid"

I just ordered an Ozone for myself. I borrowed my brother's Ozone for a 4 day trip this summer. It was the most comfortable pack I have ever used. I managed to get all my stuff inside without too much trouble. It would be nice to have a couple of pockets and attachment points on the outside of the pack but otherwise if you are looking for weight-savings and comfort this is a great choice.

I needed a bag that I could pack full of bulky things such as my coat, my violin, groceries, packages to mail, etc. This bag is exactly what I hoped it would be: lightweight, and high on volume rather than little compartments. Its got two side pouches that are enough for me for extras like a water bottle, keys, whatever. I like the fact that it is the size of large everyday backpack but can be expanded into twice that size. It doesn't obstruct my view while biking and it’s really comfortable. I'm short (4'11") and it fits my torso really well. It’s pricey and I'm still paying it off but I'm glad I took the plunge. I'm out of my car and on my bike everyday now thanks to my new bag.