I just purchased this pack, and it's maiden voyage was into the grand canyon on an overnite trip via the new hance trail. this trip was beautiful, the hike was strenuous, and the pack felt like it was hardly there. it transferred its weight (about 20 lbs full) well to my hips and legs, and didn't hang on my shoulders (one of which can be a troublesome pain) in an uncomfortable way. it never got in the way or caused me to lose my balance in precarious situations. i fit a nalgene bottle in each side pocket, and my water bladder in the pocket behind the frame. i opted for the alpine vapor instead of the vapor trail because i was concerned about durability in canyons. this pack seems to be pretty durable, and even tho i never tried the vapor trail i'm glad i went with this one. plenty of options for strapping things down and compressing. the foam in the belt, shoulder straps, and back pad is comfortable and conformed nicely to my form. i don't go thru gear like toilet paper, so i don't have alot to compare this to, but my other pack is a kelty cheyenne- a little bigger, alot heavier, and sort of cumbersome. i am a 5'2" female, and it's hard to find things that fit me well, which the alpine vapor (small) does perfectly. having one main compartment was fine- i just packed so that the things i needed to be accessible were at the top. no problem. i would consider getting a hip pack though, instead of carrying snacks and camera in my pants pockets...

I am very pleased with my GG Alpine vapor, I have used for several snowy and non-snowy dayhikes in NM and found that the excellent compression system allows the pack bag zip up to a small enough size not to flop around even when very minimal volume is being carried. I also used this pack on a winter 3 day trip in the Adirondacks in NY and it carried every thing I needed comfortably despite loading up to about 40-45 lbs. The lack of many pockets and the minimalist design proved to be no problem, I just place equip in stuff sacks and pack so that what I'll need before setting up camp is accesible. If I need another layer, I just pull out the "Clothes" stuff sack, etc. My friends with packs from Osprey, Gregory, and Kelty were less comfortable despite having slightly lighter loads. The ice axe attachment system worked well
Nitpicks: I am a little concerned about the durability of the Schoeller side pockets, they are very functional and accomodate a surprising amount of stuff, but are showing some signs of wear. Having said that, they are not torn despite extensive bushwhacking and generally rough conditions.
This is one of the best packs I've ever used and I don't give it a 5 only because I don't believe perfection can come from imperfection, i.e. humanity. Peace

Very comfortable to carry, with plenty of room for gear, change of clothing, and even works for a quick overnight bivy. Tough exterior and plenty of loops for climbing gear and a couple of ice axes. I do wish they included a removable lid with a good size pocket though. The optional lightweight one is hardly worth the extra money.