I have two scales, the Tanita 1230 and the AWS DIA-10. Actually, I SHOULDN'T have the DIA-10. The company where I was buying it from e-mailed me after I sent payment and told me that it was out of stock. They refunded my money and apologized...but I still received the scale in the mail

! Someone fucked up in their shipping department. I only wish that could've happened with the Tanita.
The Tanita is very accurate. It comes with a 20gram weight, and I also have 5 and 10 gram weights from the DIA-10. The accuracy has never been off by more than 2mg. The only problem with this scale is that, at least in my experience, it eats through batteries like a hog. Even when it's shut off, the battery's seem to whither away so fast that it doesn't make sense. I've made a habit now that when I use this scale, I take the batteries out after. It's a bit tedious, and shouldn't have to be done, so I do wish I had a plug-in scale.
The DIA-10 has basically become my ketamine scale. It is still pretty accurate, but I just can't bring myself to trust a $30 scale With fine measurements of under 25mg. The batteries also seem to last much longer in the DIA-10, so doing a lot of ket measurements isn't as rough on your battery life, and you don't need that complete accuracy you find in Tanita 1230.
I think I've had both for about a year now, and for what I use them for, I'm quite happy with both.