Re: powder measure ????
I'm in South Africa, so unfortunately I can't comment on performance of the Chargemaster with US powders.
On another point, if you do some form of incremental load development or "ladder testing" (or whatever you want to call it), you should find a "node" (or several) where small variations in powder charge are all shooting close to the same spot and often have close to the same velocity. If you load in this fashion your loads will certainly be less sensitive to a small variation in the charge.
That said, I still like to weigh them all.