I did quite a few up-grades on our BB 95 Burb TV, done at 15K it took 'til about 140k before I started realizing any actual savings. Point being it takes awhile to re-coup the investment.
I would consider other options before spending the big bucks on the GV option.
Open up the intake and exhaust, new cam, carb etc,etc.
"Sticks & stones can break your bones...and hail will dent your Airstream"
So when is this..."old enough to know better" supposed to kick in?