OK: at the risk of increasing demand for this scarce item:
Haven't had this pack in the backcountry yet, but I did travel with it last week on a 6-day field job and it performed like a champ. My retired military client wanted to buy it off me, but I can't part with it. Haven't had a chance to really put it through its paces, but carrying well over 50 lbs of field gear short distances, comfort is limited only by leg strength. On the back and hips, it feels like a wetsuit vest, or maybe a second skin. No pressure points anywhere, and I wasn't even using the abdominal plate.
Only weak spot: the fabric on the sewn-on front pouches (the side pockets are MOLLE bags) is a little light, Chafed through when I put some steel GI canteens with raised seams in them and someone loaded my pack on its front in the truck. A little adhesive patch fabric fixes that, and would recommend that for prevention. Few outside attach points: one vertical daisy chain and lower straps. No ice ax loop. COuld be easily rigged at the lower end of the daisy chain.
Interesting special gear features. Hydration bladder pouches between the external component of the hybrid frame and the pack, mesh pockets under the side pouches, which themselves are also ski slots. Internal padded radio carrier also happens to be about the size of a bear canister.
Except for that minor fabric deal, the pack is killer. Also seems to be waterproof fabric throughout, so no pack cover necessary. Huge lower compartment takes an entire GI sleep system: Big bag, liner, pad, bivvy cover. I also love the color: I like to go low profile, can't stand the bright colors in a lot of tent/clothing/bag fabric, and most camo. This thing blends in anywhere.
All in all, I am now very torn between the Gila and my vintage Serac for my HST trip this summer and definitely the JMT next year. I updated my Serac with Kelty's best civilian external suspension, but it can't touch this. Keeping my eye out for more of these for my boys
Also, I don't think is actually a Mystery Ranch suspension: I would contact Kelty directly for info on that. But it is infinitely adjustable and unbelievably comfortable.
For a Kelty in this range, I would also look at the Eagle (7850 CI, the only one listed at Kelty's web site)http://www.kelty.com/c-backpacks.aspx#subcategory=militarytactical
and the Kodiak (7203) I Don't think the Eagle has quite the suspension system of the Gila, but the Kodiak does.
Also, with troop drawdowns, more of these packs may be coming home, or unissued ones surplussed.