They are definitely worth the money, but things are a bit different for me over here.
Before I bought my Exo I bought an expensive hiking pack made by an Australian manufacturer. It is a beautiful piece of gear but not quite hunting specific, so the tripod carry options weren't quite as good and there is no option to detach the bag from the frame when hauling a big load of meat out.
Besides this pack and my Exo, I've never owned a big, expensive pack before. I've had stuff from Badlands and Blade Runner, but nothing that makes me worried about how much money I spent.
Down here, I hunt year-round, and have packed dozens of animals out with my Exo 5500 in the 18 months (or so) that I've owned it. Never an animal as big as an elk, but many, MANY times I've packed out an entire fallow deer (head, front legs, back legs, and backstraps) and it's held up perfectly.
If you hunt enough to justify the purchase, it's easy. If you really want one but don't get out all that much, justifying the money may be difficult.