The SUV Tag has a slide out, as do they all (Except maybe the 5th.. I didn't look) so it is just a tad bigger than you would expect.
I think the advantage is the way it tows, probably more stable, and the fact that you could put another trailer on it for toys etc without technically towing a double.
The wheels are up front so tongue
weight *should* be improved, and the "hitch" is 2 bars, on on each side.. making the down
weight in the back less of an issue.
Haven't seen one in person though. I wish I could.