Ha, ha...I doubt (or hope) that this doesn't catch on.
The MBs may spin slightly less, but in general terms, lofts affect spin the most. So, it almost doesn't matter which iron you decide, we can tune the lofts to meet your performance demands.
RC
As far as I know, It'll change the swingweight and overall feel of the club. My D3 head shipped with a 7gm weight in it. You can use the same torque wrench used to adjust the hosel setting to unscrew the weight out and find out which one you have. There…