I recently picked up a like new D4R...I thought it was a "Pro" but found out from Leigh that it is not. There wasn't a comparison chart between those two on the Leigh site, but I did notice you could upgrade from the D4R to the Pro by buying several upgrade kits, to include a $99 kit to change out the fingers. Is there that much difference between what I have and the Pro to pay for any of the upgrade features offered by Leigh? Thanks