Over the cab is a good option too. I have my shell primarily because the dogs go in the bed. Secondary to that purpose is keeping things dry and secure from theft, especially the off road recovery gear I keep mounted in the bed. And a the space within a bed that has a shell just has so much utility anyway.
A lot of people say i should have bought a 4runner then, but i already have a 4R and you get more space with a truck bed and shell. To match that in the 4R, you'd have to fold down the rear seats and then you've lost two passenger spaces. Off topic, yes. My bad.
Back to the discussion at hand, i think you wont regret the ARE Overland shell if you decide on buying it. Do your research of course, and whatever else you need to do, but it's worth keeping it on your list of options