I got my box yesterday and headed straight to the range.
The G-box really helped my rotation and automatically engaged the lower body more through out the swing. It also helped me to synchronize all parts of the body more. I also felt more powerful from the top after just a few swings - both from better rotation but also from using the lower body more efficient for power. Didn’t use a trackman so not sure if it was feel or real.
I love it and can’t wait to try it in a TM