This is an excellent lightweight frame pack for day hikes or lightweight camping. I have taken this pack on a 4 day trip through Glacier as well as a long bike trip. This pack worked perfectly for both trips and I couldn't be happier. Although there is not much to the frame and suspension, it carries weight very well and is very comfortable. This pack remains lightweight while still keeping convenient stash pockets and gear loops which really helps keep gear organized and accessible. My favorite feature of this pack is its breathability. The mesh back and straps allow sweat and moisture to escape quickly without compromising shoulder and waist strap comfort. I would definitely recommend this to anyone and everyone. Definitely my favorite pack for day hikes and lightweight camping.

When I read about this pack I was amazed. The weight, the features, the fact that it was listed in NatGeos Adventure gear of the year 2009–What more could anyone ask for? The pack has been lauded by one and all at only 1lb14oz it was supposed to compete with some of the best frameless packs. When I research gear I put the same amount of effort into it as a heart patient trying to figure out the best possible hospital for a heart transplant. I must have studied every angle of the pack and admired the youtube marketing video put out by Osprey more times than I’d like to admit. Plus Osprey is a great company with a wonderful reputation standing firmly behind each and every pack they make. Researching the Exos 46 I noticed a difference in the weight posted on Ospreys site it was now 2lb 5oz for a Med. Exos 46, so I immediately called osprey to investigate and it turns out the weight of the pack changed in production – and it is 7oz heavier, the newly listed weight is in fact correct. I forgave the discrepancy since After all my research I was convinced my 1 year old model of the Gregory Z55 had become yesterdays news and needed to go. I didn’t care that it served me well in the wilds of Wyoming - NatGeo picked a new golden child and the EXOs 46 was going to be mine. After deciding that the 46 would suit my sub 10lb base needs I ordered it in Med. – I was on the border of sizes so I went with the pack that would weigh less. The pack arrived from backcountry and regardless of how many packages I get from BC it’s always like Christmas in my house when they arrive. I took out the pack marveled at the pockets, the straps, and the brilliant ingenuity. This was certain to be the Lexus of backpacks. Deep down I marveled since I was about to become the envy of every backpacker on the Appalachian Trail.
After my extended excitement it was time to load the pack. My goal was to place a reasonable burden of weight in it to see how it feels and performs. I loaded it with approximately 25lbs of gear, and excitedly strapped the Exos pack to my back. In short order I began to feel a hot spot on my shoulder – Is this a consequence of age? Had I aged that much since last fall? I must have tried adjusting the straps every way possible for at least 45 minutes. Surely this can’t be right this is the must have highly acclaimed pack, this pack sells out and fast! Everyone can’t be wrong, can they? Finally I began to accept and realize that if this pack caused pressure points in my home it would be a disaster one hundred miles from nowhere. The only logical conclusion was that I had obviously ordered the wrong size – OF COURSE! The pack I need is a large, how could the brilliant folks at NatGEO be wrong – after all my Z55 had been the very essence of comfort. I am sure many are asking why I decided to get a new pack – well the logical reason is my wish to further cut down on weight. Going UL for me is not a religion as it is for other fanatics – it’s a matter of convenience and comfort. I enjoy being able to bend down on and off trail, I love the ability to jump over obstacles, and run through streams – the less weight the more nimble I am. This all equals more comfort and joy when out and about. So I ordered the large. It came today. I noticed the same hotspots where the shoulder straps dug into my skinny frame, plus the pack does not hug the body. I tested it on my steep stairs and the pack bounces no matter how tight I make it, plus the more I tightened it the more the straps dug into my shoulder. Finally compared to the z55 less of the weight was transferred to a profoundly less beefy waist strap, causing my back to literally shoulder more of the burden. I really wanted this pack to work, but sadly the comfort is just not there for me. So I unloaded the Exos 46 and transferred all the contents to my Gregory Z55, I needed to see if my body and not the pack had let me down. So I removed the lid on the Z55 and packed it with the same weight plus I will trim all the straps to the bare minimum this season. Sure it weighs a bit more – but the goal for this hiker is and always will be maximum comfort while hiking. I’m sure you all know what comes next – the Z55 was a delight just as it was last year. Also I have seen it come up a few times on SAC for like $100 or less and as far as this hiker is concerned it’s a steal.
Here’s my point – don’t fall into the trap we are all so guilty of. If it works you don’t need to fix it. Similarly I have been debating buying the lauded NEOAIR we are all aware of the space station technology involved with it that people talk about. I was considering the NEO while Ignoring that I sleep perfectly sound on my Big Agnes Aircore size small at 16oz - it has always completely covered this side sleeper. I went to my local camping store to marvel the NEOAIR in an instant a salesman sensing my desperation for newer and better was hovering over me as I felt the material. I couldn’t help but notice that I would be far more comfortable relying on the BA Air Core since the material is strikingly more rugged. Does the NEOAIR have a true 2.5r rating like the salesman was touting to me – I don’t know – but then again I doubt most people can even define what an R rating is exactly. I slept warm and like a baby on my BA AirCore in 35 degrees plus it never busted or deflated, and it is easy to fill and only cost me around 40 bucks what more could I ask for?
I feel like my rating is generous since for me the pack is not adequate, only I am sure there are others who will not notice the same degree of discomfort. As far as backcountry is concerned they get five stars from this writer always.

Amazing pack, and all of the straps are excessively long and can be trimmed to normal lenghts for more weight saving. I really wanted this to work. Loaded it up with 25#, and it's like the hip belt would rotate down in the back, and I would end up with more weight than I wanted on my shoulders. The vented backpanel was great in the desert at Guadelupe Mountains NP, but I kept tightening the hip belt to try to get it to work, and it felt like the 1/2" strap would cut me in half. Maybe it's just my build, a buddy tells me it works great for him.

Solid and Awesome!

Like other people, I have been waiting for the perfect pack that is lightweight, and full featured. If you have a look around the ultralight backpacking scene it can be a little daunting. Cutting straps, counting ounces, and getting it down to the purest elements of what you need can add up to a lot at once. Going light is absolutely the way to go, but getting there takes some time, and you want to make sure you do it safely without jumping into gear that is too flimsy and will let you down when you eventually add a few extra things at the last minute.

This pack is pretty bare bones, when you look at the fine features. They have cut weight everywhere...little compression straps, minimal hip belt, lots of mesh, and little buckles...but they are the experts and all those little things mean a really light pack, that has most of what the others have.

I used to have an old Gregory that was like 5 pounds, and by switching to this, It's like throwing in the sleeping bag, and pad at no extra weight cost.

There is lots of nooks and crannies to organize and keep gear where you want, it has a frame for support, and it's just made well and has everything I need. When I first used it, I kept saying "Damn...this thing is great"

I'm super happy with this purchase.

For sizing...I"m 5'11 about 165lbs and got a medium and it fits. I can fit all the gear for 2-3 days very easily and keep my gear to the "lightweight" league, nothing too crazy. I managed to fit a bag, pad, tent (sierra designs lightning with fly) cookware, stove, clothes, food, water, bear hang, first aid, you name it, it fit in there.