I end up not ordering the bungee because I read about not strong enough to hold down heavy laptop bag. However, I did order a few of the attachments to try it out.
The travelon work ok, but it is too long for my Tom bihm. My western flyer would sometime touch the ground.
I found something call link my luggage, it is a loop that go over the luggage handle. In which might give better support. But I just gave away my carryon, until I find a new replacement I can’t test this setup again