They look like rear shocks off of a sport bike. This set up dosnt do anything productive. All it does is shift the center of gravity in the rear of the car higher up. I dont see any other real benifits of it.

I consider unprung weight to be stuff outboard of your shock system. Like wheels, calipers, rotors, uprights. Its all weight that isnt directly conected to the shock but the shock has to support its weight. The shock is tied directly into the chassis which means its supported by the chassis. Thats like calling the subframe unprung weight.