Ended up with a Nissan Murano, which seems a lot less spacious than an Explorer or Grand Cherokee.
It was a nice enough car to drive but felt a bit short-changed as the Murano seemed more on a par with what some of the other rental companies (Dollar and Alamo) class as an Intermediate SUV, such as a Rav4 or Equinox, which would have cost substantially less to rent.
As I am UK based I don't have a great knowledge on US vehicle types. does this sound justified or am I being a whinger!!