Dang, nicely done!
I need to change 8-10 or more sets of tires per season (track riding) and so I purchased this a few years back. Paid for itself in no time.
Personally, I dont' see any big advantage to pre-balancing the wheel itself, but to each his own.
ps. motorcycle tires don't need to be balanced as precisely as cage tires. It's the physics. Does not mean to be sloppy, just don't try to balance to 1/4 ounce.