I have the Tristar with the Tom Bihn Absolute strap. As advertised, it does a great job of distributing weight and "lightening the load". However, unless I use it cross-body, it slides off my shoulder, necessitating a lot of near-convulsive repositioning maneuvers. Generally, I give up and grab the handles. Then the strap drags. The strap weight is not inconsiderable, so I've just taken it off. Now I use one or both shoulder straps and find it much more comfortable in backpack mode if I don't have my second carry-on rolling briefcase to tote it on.
I'm glad I don't have the Airboss as I'd be stuck with some kind of single shoulder strap. (Plus, both the Aeronaut and Airboss probably hold more than I'd want to carry.)