I own two Revolutions and one Outback. The Outback was my first kayak and loved it. The Revolution though is just easier in my opinion. Especially when paddling. Although I have only flipped a kayak once it was in one of my Revolutions. I was new to kayaking and leaned too far when I found myself going into the overhanging vegetation by the bank. I don't think the Outback would have rolled on me, but its hard to tell. In any case I learned not to lean and to sit up (or at most just lean forward and down) and take what is coming to me if I end up going into overgrowth on the bank. One of my kayak partners has an Outback and I always notice that even on perfectly flat water the Outback hull slaps the water and makes a fair amount of noise even when casually peddling. The Revolution is much quieter as it cuts through the water easier.
I can't use the drink holder in the Revolution though, because my leg hits it with every peddle stroke. I end up using the bungee over the access hatch to hold my water bottles. This is not an issue in the Outback.
Like anything else it will come down to what you value as being the most important features, but you could always buy one of each!
