I have not used an Exo per se in the field, my friend had one for a couple seasons then switched to Kifaru. I have the Kuiu in a 6000, 3000, and 1800 size and I have a Kifaru with a Bedlam and a Fulcrum bag. I used the Kuiu for 5 or 6 years, packed a lot of critters out with it, have had the Kifaru Fulcrum for about 4 years, packed a lot of critters out with it also. I like the Kuiu for scouting and day hikes because it is light!
Personally If I only had to have 1 pack it would be the Kifaru Fulcrum. It tends to carry everything a little more comfortably and is built to a higher quality in my opinion.
As everyone has said a pack is unique to you, you have to try it to decide for yourself if the pockets, layout, weight, adjustability etc will work for what you want. (Utah Sportsmans Expo is really good for this reason.)