This is a truly great backpack. I'm 5'8", about 180 lbs and I use the medium, which fits perfectly. I've loaded it up to 40 lbs, and done 15 miles comfortably. I bought this to replace a much heavier Gregory Pallisade which I've had for years, because my knees aren't what they used to be, and I'm trying to cut down on the weight. I opted for the Atmos 65 because it has the sleeping bag compartment, but if that's not important to you, you can save a few ounces and go for the Atmos 50, which doesn't have the sleeping bag compartment and is slightly smaller/lighter.

Suspension: Super comfy Air-Speed mesh backpanel, for max air flow. Soft but suprisingly rugged waffle-foam for the shoulder and waist straps. The frame does cut slightly into the pack, but this is LIGHT YEARS ahead of the 2008 model. The 2008 model had a 3" thick air space, and the 2009 has a 1.5" space. The result is much more internal pack space. If I have a full load, I usually hang my 100 oz. camelbak inside the air space (the pack comes equipped with special clip designed for this purpose, and can be used to hang items inside the main pack, or in the air space). Keeping the water in the main pack takes up space, whereas keeping it floating in the air space 1) means you can pack what you need without worrying about a bulky hydration bladder, and 2) keeps the weight closer to your back (easier on back and knees). The air space is also great for stashing dirty clothes if you have too.

All of the other features are extremely well thought out, durable, and pretty damn cool. Love the zippered waist stash spots, the backpanel access points, and I've even used the trekking pole elastic cinch on numerous rock scrambles, and once when I snapped a pole. Plus, I've used it as a carry-on to Italy and Seattle...and this baby looks good everywhere!

Bottom line: Awesome pack.

I was a little hesitant buying this without ever trying it, but my fears were calmed after the first trip with this bad boy.
The shoulder and hip belts are extremely comfortable, and the little holes in them help from getting too sweaty under the straps. Super durable material, sheds water well too.
My only vice with this pack is that it's not very expandable, the pack material doesn't stretch much, so if you have a big load, you most likely will be strapping stuff on the outside. It's nice though because it makes you cut back on unnecessary items. overall, excellent pack, lightweight, bomber construction. buy it with confidence

The Gist Of It ::
I purchased the Osprey Atmos 65 Pack to replace an old Osprey pack. I was simply looking for larger capacity & function - I gained quite a bit extra. The Atmos 65 pack fits all my needs; the Medium fits like it was made for my 5'7" 115lb frame, holds all I can imagine & then some. Every inch of this pack was well thought out, made to be very convenient & common sensual, all the attachments are there for a reason (you actually use them! what a concept). Even down to the color choices... thank you Osprey for not assuming all women love baby blue & purple!

*The first test - out on a 3 day 27 mile backpacking trip to the San Rafael Wilderness, I was nothing but impressed. I nearly forgot about it due to its forming comfortably to my back & the all the possible adjustments available to lighten the load on my shoulders & hips. In the high heat of mid-Summer, the air-core ventilation was a life saver.

*My second test was a week long road trip (CA to CO) - no hotels, all camping (car/light trekking) & it doubled as quite the efficient luggage, simplifying the packing & unpacking process with it's many handy zipper compartments. I over packed just a bit & never really noticed the extra bulk with use of the compression straps.

Bottom Line::
The Osprey Atmos 65 is that one in a million pack that has everything you need & nothing you don't - I have zero complaints. Big enough for weeks of trekking & compressible for a weekend trip, this one was intelligently designed for sure!

I got this for use as a summit pack and got this for the ultralight weight, although it barely fill the role. Construction is top notch as is all Osprey packs, and it will definitely last forever. Zippers have great pull loops that stay open and are easy to use with gloves. I will probably replace it with something else later as the curvy back might be great for hiking in the heat, but it just collects snow on Alpine runs. I would also point out that although it says 65 liters, it feels a lot smaller because of the curve pushing into the bag space. Makes packing more difficult. The 2009 version have changed this by having far less curve, so maybe it's better. I wouldn't plan on doing more than 3 days with this pack unless it's warm and you aren't packing many layers. Only Osprey pack I have owned that I regret at the moment. If I had it to do over I would probably buy the Osprey Variant but then again I wanted a summit pack and that didn't exist at the time. Too bad Osprey won't let me trade up.

As usual, as with all Osprey packs, attention to detail and construction on the Atoms 65 is excellent. For me, Fit was a little bit of a problem. I'm an "in-betweener". My waist is now all the way up to a 35 (winter was brutal on my figure!) and my torso length runs 19 to 21 depending on how I'm measured. AFter exchanging packs a couple of times, I decided the Large was my best option.
I just recently did a 3 day trip and found the pack to be good, but not great. For me, the pack became uncomfortable when loaded above 33 lbs. The belt just doesn't seem to be enough... above 33 lbs the pack transfers more weight than I like to my shoulders. The ventilated back mesh does its job; No sweaty back with this pack! I found the bag allowed better organization through the use of it's many pockets! I especially liked having the option of hanging my reservoir either directly behind the back mesh (where it takes up no pack envelope space), or in the traditional spot inside the bag. Nice Pack... might have been a 5 star pack if I wasn't an in-betweener. Note: This pack is NOT an adjustable torso length type.

Recently got this bag for spring and summer. Its very comfortable and hauls gear for three or four days. I wouldn't go much over forty pounds, but thats not what it was made for. Really like the trekking pole feature and the outside pockets are perfect for rain gear.

Very comfortable and light. Has a lot of useful pockets and features. Only complaint is the curvature of the back makes the main storage compartment a limited. With a sleeping bag, pad and bear canister inside, there isn't much room for other stuff.

I bought this pack for extended trips. I love the weight, suspension, numerous pockets, hip pockets, and mesh back. I have used a 2L camelbak bladder in it and it works great. Sorry to Osprey move their productions overseas, but I guess it had to happen to keep costs in line with competition.