Update: After I told them I didn't want the second 220, they replied with a terse "OK".
Then my one 220 arrived in the mail, USPS, from an address in California. No second one. So it appears they were able to redirect the package after it was shipped, and I don't have to send it back. It also means I have no reduced-price scale to offer anymore.
The 520 I ordered at the same time has not arrived yet. It took them a day to ship that out after I pointed out their error, so hopefully it will be here soon.
The 220 arrived in good shape, nicely packed, nothing missing. The swarf cover appears to be well-designed. No instructions at all of course, not even in Chinese. Manufacturing quality seems great, though function is mostly all I'm interested in. But the parts look nice.
I hooked it up to my new T-DRO adapter, set the magic number to 5080 in the software, and it appears to be working perfectly. Proper calibration will be done after it's installed on the mill of course, but it's correct to the precision of the ruler on my desk.
Mine didn't come with any angle brackets or extrusions for mounting the read head to the mill base, or the scale to the saddle. (This being my Y axis.) Who has ideas for where to get some? I see some "how-to" videos where they used bits that shipped with the scale, with adjustment slots machined in them already. Purchased from some other vendor no doubt. I have no problem ordering pieces from Online Metals or ebay and machining my own slots, but being lazy, I'd settle for some pre-made brackets, if anyone knows of a source. RF-30 being so dang ubiquitous, someone should sell a turn-key kit!