Easy to use.
I had been looking for a solution for quite some time. I often travel by train, usually with a check-in bag and both a carry-on bag and a rolling computer/electronics/accessories case. Since my luggage is the spinner type (with four wheels), the tether system does not work.
I had been placing the computer case on top of the check-in bag and trying to attach it with various straps. It took a lot of fussing to get it on before the computer case fell off and never worked very well.
The "Add a Bag Bungee" is simple to use and very effective. I like the fact that I can first attach the bungee to the suitcase. Only then do I place the computer case on top of the suitcase and simply pull the bungee over it and around the suitcase handles. Once on, it is a matter of a few seconds to pull the supports where needed and tighten the bungee. Fast, easy, and it holds securely. I love it!