My Mystery Ranch Blackjack showed up two weeks ago. Haven't been out in the field with it yet, I'm waiting to find a SCBA shop that'll refill the canister so I can test blow it.
First impressions though.......WOW. This pack is BOMBER. The fit and finish makes my Dakine packs look like they were made my a 2 year old in Indonesia (well, maybe they were). It does feel kinda heavy when lifting it (it's one of the heavier airbag packs) but the weight almost completely disappears once you put it on your back (even when loaded). With the custom fit climbing style frame, it carries very very VERY well. Definitely large enough to fit gear for a hut trip at 42L, but compresses down real nicely if you're just doing sidecountry laps too.
Overall, this pack lives up to Mystery Ranch's and Dana's reputation. Very solid and well built pack. Made in 'Merica, bitches!
I'll get some pictures for you guys and a video of the first test blow......