I think I saw that site before..
the videos look familiar.

To tell the truth I have some doubts about the design and if it would be comfortable or cause pressure points in the armpit or over the collar bone.
Possibly may cause blood flow in the arm pit area to stop too..

it's almost something you could try with a stretchy band yourself if you have one long enough [most PT places have those for sale].

I just have my doubts and I think it is over priced for what it is.

If they have an easy return & refund policy then it might be worth trying . As long as you can get your money back if it doesn't work for you.

It may be aimed more for "normal " healthy folks than ones with TOS or similar conditions.