Full disclosure: I sell Camelbak "military" packs and hydration gear.
I have the Tri-Zip. The reason is appears much like a Mystery Ranch pack is that it's a collaboration between MR and CB, the only one left after they severed the relationship which brought many of MR's packs to the commercial market.
Overall, it's a nice pack. I've had it about 2 days, and haven't had a chance yet to play with the suspension, so I cannot comment on that. It comes with a standard "Omega" 102oz / 3L reservoir. The main compartment is just that...one big compartment with two small zippered mesh pockets on the inside, just below the top lid. There is a zippered slot pocket in the lid, lined with microfleece.
There are two side pockets on the outside, on the left and right side. On the right side, as you're wearing it (or looking at it from the back), the pocket is more an "admin" pouch/pocket with pencil holders, etc. On the left side (as you're wearing it, or looking at it from the back) can fit a Camelbak 750ml bottle with Camelbak bottle-top, or a 1L Nalgene bottle with standard screw-top. Note that in either case, the pocket configuration expands to the inside of the pack, not the outside, so if your main compartment is stuffed to the gills, it might be difficult to put a Nalgene in it.
I plan to do a bunch of hiking with it over the next couple weeks.
Hope this helps.