RE: ChargeMaster
I picked up the chargemaster mainly for handgun and large caliber rifle reloading since my Redding BR-30 has a limited charge range. I've found it very handy; it's obviously not as fast as pulling the handle on a typical powder measure, but I just modified my reloading process to perform the powder charge and bullet seating steps in parrallel (seat the bullet on one round while the powderdispensesfor next). I've found it to be fairly consistent (+/- .1 grain) and accurate (I've checked loads on a more accurate scale that is +/-.02 grain). I'm not ready to use the chargemaster for everything, but it's great for high volume reloading.
The biggest con (besides price)in my opinion is removing the extra powder once you're done. Dispensing the leftover powder is a pain and always results in some spilled powder and takes longer than it should to get all the powder out of the unit (but it is great when I'm using the same powder, but a variety of different charges- so much faster than fiddling with the BR-30 micrometer to get exactly the right charge). This alone prevents me from using it when I work up new loads with multiple powders; I'd spend more time dumping out one powder and cleaning the unit than actually loading rounds.
My .02