I have used the X2, including to pack out a whole boned out deer and for elk quarters, the old pop up 18 ( didn't get to carry a critter, but did try 80 lbs qwickcrete mix), a new pop up 28 (no critters yet) a stone glacier r3, mystery ranch pinter and sawtooth, and kuiu icon.
For what you are doing, especially in brushy forest, I think that the pop ups are it- I particularly found the 18 amazing in that unloaded, no frame part stuck up anywhere, it was unobstrusive, and you could crawl through and under blow down without getting hung up- yet it handles a reasonably big load pretty well when extended. Not as good IMHO as say a pinter on the guidelight frame or the stone glacier, but handles it well. Newer one has frame update, no 18 anymore. IMHO. I would recommend a pack with a full size frame if you were backpacking in, then day hunting...or maybe if elk was #1, vs deer. The thing with the x2 is no load lifters, makes a big difference to me, but I am old beat up, and also used it after having used better packs for big loads. I also did break it on my 3rd elk quarter load- popped a rivet. X2 is a decent day pack, not as good for heavy loads like meat imho- although for a 1st smaller load out, and then returning with a frame, it is ok. A couple of tge newer eberlestocks with the frames and detachable bags look ok, haven't tried them.
Lots of good advice here. I use the old, no longer made Pop-Up 18 as my day hunting bag in SE AK, in some of the wettest and thickest conditions to be had. It is indeed unobtrusive and easy to maneuver in. I've hunted this country for nearly 20 years and have gone through a number of packs trying to find the right one, and the pop up is just the thing for still-hunting or an alpine day trip. I find it has just enough space for the things I need to carry, yet I can pack up to two deer with it. That being said, it's maxed out in both respects as my rain gear needs to be strapped to the outside and two meat bags with a deer apiece is the limit for both space and weight. I last used it to pack two deer a couple weeks ago and decided whatever the load was, it was about the most you could comfortably carry on that frame. When I got home, the pack weighed 78lbs. With my old MR Nice frame 6500, 78lbs is more comfortable to carry for long distances, but for the day hunt mission the pop up is much better. If I somehow lost the 18, I'd buy a 28 to replace it in a heartbeat.
