Years ago I bought a PACT BBK digital scale and paid ninety-odd bucks. It has worked OK but lately I have noticed some new digitals offered in the $30 range. Weighing powder is serious business, and I have wondered whether such low cost units would give decent performance.
I have now had a chance to test two examples, both brand new, of this scale class. I tested them with weights from a set of standard analytical weights sold by E. H. Sargent, which I obtained some years ago when a Chemistry Department was getting rid of stuff it no longer needed. For scientific purposes the set is denominated in grams, but this is easy to convert if you know that 1.0 gram = 15.432 grains.
I had excellent results with the DS750 scale sold by Frankford Arsenal. It is a slick and accurate little unit (see the pic.). The gram weights and grain equivalents that I used are as follows: 20 grams (308.6 grains); 10 grams (154.3 grains); 5 grams (77.2 grains); 2 grams (30.9 grains); 1 gram (15.4 grains); 500 milligrams (7.7 grains); 300 milligrams (4.6 grains); 200 milligrams (3.1 grains); 100 milligrams (1.5 grains); 50 milligrams (0.8 grains); 30 milligrams (0.5 grains). The grain equivalents are calculated to one decimal place since that is all these scales will give you.

The DS 750 quickly gave essentially these values with the test weights, placed either directly on the surface or in a 43-grain tared out powder pan. Very occasionally, a weight registered .1 grains light. The scale was easy to calibrate and the zero point and all weight values were very stable. Upon removing a weight, the scale immediately reset to 0.0, every time. The 30-mg weight was the lightest that the scale would respond to. A 20mg weight would not register a value. The 30 gets you down to .5 grains, however, and shows that this scale would be adequate for pistol work.
I had much poorer results with the other new scale. I won't reveal the make as I don't want to reveal harmful results on the basis of one example. The problems were a lack of stability and accuracy. The scale would often return a weight value .1 or .2 grains light, and the value would then drift downward. The 1-gram weight registered 15.4 grains when placed on the pan, but would drift to 14.8 grains in one minute. It could work fairly well in the 30-200-grain range, but I would have no confidence in it for pistol work.
What you can take away is that low-cost scales will vary in performance, and the DS750 is a very good one. What you want, if you are allowed to test one, is stability of the zero point and of the weight values measured, accuracy, and accuracy that is the same throughout the range of the scale. Sorry this is so long, but I thought you might be interested. Anyone else have any experience with a cheapie scale?