I recently got the same from a diff source. It isn't repeatedly accurate to the mg as near as i can tell from detailed experimenting but I can possibly help you with yours. The little sample dish that comes with it does not fit well on the load cell. (the part the senses the weight) Try finding a small washer that is about the same or slightly smaller than the center bottom of the sample tray. Glue it there with a light duty glue. Alot of the repeatability problems seem to come from the dish not sitting correctly. The washer centers the weight on the load cell. After doing this, I find mine reliably repeats with in 2 mgs.
The issue with mine is that the initial reading climbs through the numbers once made making for a hella fun time when trying to dose in the milligram range. Mine appears different to the one linked on ebay there as it does not have the American Scales logo but a different thing in red, it might say mg scale I can't remember. I have often hypothesized of it being a counterfeit scale made in Asia purely for the purpose of duping those determined to buy the cheapest model available. Seriously this set of scale appears to run from five pounds upto around 50!
Best advice here. 2c-b is amazing, I'd probably split it into 2 piles and do 50mg :sunny:. But I'm experienced with it, 20-30mg is a good starting dose.
Are you referring to the phenomena wherein your field of vision distorts, in the fashon of a sucking/stretching motion in one direction, and strobes violently, possibly with colors also changing? I had this happen while candyflipping, though I've never done molly with out cid. It was quite fun, but i'm not sure it was a twitch, or anything to do with my eye... Pretty sure my eyes where wide open in awe the whole time. I dosed what I was told was between 16 and 18mg of 2cB, which I am aware is light, and had none of this sort of thing. Mostly a generally molly like feeling, though maybe actually a bit speedier with less body sensations, and while outside at sunset, there where distortions on distant objects, and some close ones. At one point, a blunt had a glowing blue outline around it, that sort of thing.
Usually when I come up at some point my whole body is shaking. My eyes wiggle occasionally like molly. Psychedelic seizures ftw haha.