I can confirm this works as advertised. Getting the belts in and out was a bit difficult at first, but I've got it down now. It seems like it would stress the seat leather less than a normal booster would. My daily driver has dents and marks from the more permanent boosters and child seats.
Interesting, did you order online then? I thought they were only at the pre-order stage.
The issue with the three-wheeler is that no other booster seat will fit, the seats are too narrow