The Sterling line was designed to be lighter than their other lines, while still towing most common toads. It is made of aluminum. For heavier toads, look at their Blackhawk line. The Blue Ox do look beefier, but weigh more. Had one on my Vectra, worked okay.
As mentioned, the Sterling has a new, improved release system. The old one was about as tetchy as the Blue Ox. I imagine Blue Ox has something easier to release as well, but don't know how much it weighs.
2003 Alpine 40FDTS (400HP)
Long Beach, CA