It would really depend on the type of hunting that your doing. I only have one kifaru bag (just switched over this summer to a duplex frame and reckoning). Technically we have three. I have the reckoning, the wife has a woodsman, and I bought a rambler, but it hasn't even been tried yet. . For me, I looked at a lot of their bags. My hunt type was going to be a 5 day backpack in style hunt, so I wanted a do all bag. One that would hold 5-7 days of gear, and would collapse down for day hunting, be able to carry spotter and tripod, and carry meat when needed without having to go back to camp or the truck to get a meat hauler pack. For me....that choice was the reckoning, with guide lid, with medium belt pouches attached to the main bag, a Nalgene/holder on the left side of the belt, and a med belt pouch on the right, along with the gun bearer for ease of carry.
The pack easily carried my 5 days of gear and was more comfortable doing it than with my previous pack (eberlestock dragonfly). While hunting it collaped down into a day hunting set up with no problem. The other bags I looked at were the EMR2, the Fulcrum (new version of same bag) and the cavern/crater. when I say "looked at" I mean on youtube and on here. We now have a woodsman for the wife, and it works great for her. The center zip on both of those bags is one of the big reasons we went with them. The woodsman is about 13 ounces lighter than the reckoning. If you don't as much room for gear, its a good choice and lighter than the reckoning (assuming you don't need to carry as much gear). I only have experience with those two bags, but maybe that will help you some in your decision. I was on the fence for a LONG time trying to decide. I don't regret my decision though! It was expensive up front, but it worked out real well and was an upgrade compared to our previous bags.
As another person mentioned...go to youtube and do a search for the bags you are interested in. There are lots of reviews of them out there. Aron (from kifaru) also does in depth explanations of each bags layout and function. Jordan budd also does some really good reviews on here and on youtube of a few of the bags. Covers the gear layout, breaks them down into "day mode" and makes comparisons. Enjoy the ride!! LOL