I've owned a ton of packs over the years, for both hunting and backpacking. But I think the OP is specifically interested in the hunting variety, so I'll keep it focused on that.
Kuiu Icon Pro 7200 and Kifaru Reckoning
My first "hunting", or load-hauling pack, was a Kuiu Icon Pro 7200. I wore it for one season, on a 7-day Colorado elk hunt, but also used it a ton to train in prep for that hunt, mostly on a stair climber, a couple "shake out" trips, and on the treadmill in the basement, all of which was under load, usually 30-50 lbs. I went into the backcountry at around 55 lbs (rifle, gear, food, water, etc). Primary reason I went with Kuiu was simply the price point of the pack. I think I got the entire setup for around $300-400 or so brand new. But at no point was the pack ever really all that comfortable. I spent four years in the Army, wearing heavy loads, so I figured this was more or less normal, and the cost of doing business in the backcountry hunting game.
Kuiu Icon Pro -
Pros: price, style;
Cons: not comfortable
And then I borrowed an older (2005?) Kifaru pack from a friend and shortly thereafter hit up Aron Snyder on Instagram with a couple questions. He encouraged me to give him a call and I did. He was incredibly helpful in answering questions about pack fit, torso size and body type and how that affects pack fitting, etc. Bottom line: I ended up purchasing a Kifaru kit - Duplex frame, Reckoning bag, couple belt pouches. The difference was remarkable. I haven't packed out an animal yet, but thus far, I've been able to load it up to 70-80 lbs of sand and, while its not necessarily "comfortable", it's not really uncomfortable, either. The materials are incredibly durable; all Kifaru stuff is well-built, made in America, etc. And the customer service is top notch. The downside, of course, is the price point. I think I spent close to $900 for the setup, which included a free upgrade on the lid due to the cheap lid being out of stock. Kifaru packs are typically on the heavier side, too. Think my pack is prob around 7-8 lbs empty. But, I consider that a worthwhile trade-off for durability and comfort.
Kifaru Duplex Frame and Reckoning Bag
Pros: durable, comfortable, well-made, good fit.
Cons - price; heavy; another downside with Kifaru can be availability. Most of their stuff is made to order, so if you need something in a hurry, you made be out of luck.
