Resolution and accuracy and linearity is not the same thing not even remotely. while the resolution on the display is 0.001 grams. The linearity is not that. And the scale is not accurate enough to even reliably weigh one kernel of powder. It accurately weighs +/- 2 kernels of powder either direction, in a pristine lab environment where it is tested for linearity. Not in whoevers basement/garage in any condition (temp,humidity,draft,emc etc.) A varget kernel is ca 0.02 grains. The FX 120I resolution is 0.02 grains, in that grain mode. The confirmed linearity of the scale is +/- 0.04 grains=0.00259 grams. The class 3 calibration weights are already way more accurate then the scale is. And yet i would still agree that the M2 calibration weights that follows the scale is plenty accurate. Aslong as it does'nt get handled badly it will still calibrate that weight as 100 grams always wether it is + or - 0.016 grams. For a reloader that uses that weight on the same scale every time. And develop his loads the same way. That load in x amount of grains will come out the same every time +/- 0.04 grains, and there will never be a real gain in buying a better quality calibration weight for practical purposes. And no there is not a way to tell reliably that the scale is off by 0.02 grains, because it is simply not that accurate to begin with. Anyone who wants to reliably and accurately weight one kernel of varget or similar, will have to buy a better and more expensive scale from the get go.