I too use that same scale . . . highly recommend it. Had it for years and it still works great.
If you notice in the picture of it there is a small tare weight in the upper right corner - I keep my tare weight in a separate location, and keep one "tare pellet" (happens to be a JSB 18.1 grain one that weighed 18.5) and use it to check the scale with, since it is in the range of what I normally weigh anyways (10 grams seems high for us). Always get a reading within 0.02 grains with that one, so I know it is very repeatable - can't comment on the "accuracy" though, as I have no known true reference other than the stated weights on the tins of pellets, but it seems good.