I missed out on these on their first run, but fortunately caught one on their second run. For years, I waffled on picking up a Maxpedition Proteus Versipack - my bother had one, it was a neat little pack, and it filled a very specific role. I never did for a variety of reasons, but I knew I wanted this HPG buttpack. (My spell check keeps trying to change buttpack to buttock.) I was not disappointed when I received this item.
As with all of HPG products, the finish is quite nice and it is a handsome little bag. There's a carry handle that is quite well done, and it seems to be a slightly softer material which is just ... nice. I'm a big fan of grab handles on bags, as I'm frequently grabbing them without shouldering/strapping up/ whatever when I'm moving a short distance.
The PALS on the sides is nice, and a 2 pistol mag pouch from BFG fits nicely. Yes, it is empty. I don't know what to put in it, I just thought it'd be handy to have there.... As you can see, this bag is quite thick. Which is wonderful. It seems about perfect, thickness wise.
Opening the bag reveals two wonderful things. The first is the massive cavernous interior, and the second is an awesome little zip pocket on the lid.
The zip pocket is quite nicely sized - here's what's I've put in it, without stuffing it: soap, bug dope, chapstick, a bajillion chlorine dioxides, spare batteries, TP, compass, lighter.
On to the inside. This is by no means stuffed, but it is comfortably full for me. The tan/khaki pouch has a Trangia alcohol stove, 3 2-oz fuel bottles, an Emberlit Fireant TI (folded), ferro rod, matches, lighter, and dryer lint (awesome fire starter, esp when combined with wax or vaseline). The red pouch and the green pouch are both from ITS Tactical, 8.5"x6". The red one has a SOF tourniquet, giant sharpie, and an IFAKed Up kit from Travigate (hilarious name, and Jeff is good people) - mostly for boo boos. The green pouch is full of daily sundries, like pens, cords, spare phone battery, chapstick, flashlight, etc.
In one of the pictures above you can see I can also fit a spare pair of wool socks, but I don't normally keep them in there - adds a little too much bulk, rolled up in a plastic bag. You'll also see a headlamp, and a little box full of coffees and teas (I like my morale boosters yo).
Essentially, in this tiny little bag, I have a lot. Add some water, some food, and some shelter/insulation and you're good to go. Incidentally...
This is a 10x10 tarp. Strapped to the top of the pack. Ideal? No. Possible? Yes.
(Oh, and on the outside, under the PALs-cut hypalon-equivalent, is a Mora. Why? Because fixed blades are great and Moras are handy... Don't judge me.
This works great in conjunction with a prairie belt, although I may be a little too short-torsoed to use this on a belt with a Tara. Doable, but not ideal for me. If I did that, I can easily stash water on the belt, put bottles in the Tara wand pockets, and throw some insulation in there, and strap the tarp on the outside... Ideal? No. But doable. If you need to. Why would you need to? I don't know. Go come up with your own survivor fantasies...
Haven't had a chance to use it with my Ute, so no comment there. But at the very least it'll work as a fantastic pullout, and I'd imagine work pretty nicely as a day bag on your belt if you leave the Ute bag in your base camp. If you do that sort of thing. I imagine it could be easily reconfigured to work as a nice little precision rifle bag, if you're not so inclined to use a kit bag for that.
One last thing - the shoulder strap it comes with is excellent. And I've found it stores very nicely in the slot that holds the frame sheet. Just sayin'.
P.S. Hills... Stop coming up with awesome products. You're taking all my money and I'm not even upset about it!