And not just on eBay, either.
Thanks to an inquiry, I learned that a Canadian-based company called SysComp is reselling the Mastech MS8226 as model number DVM-101. They don't even attempt to re-brand it, they just re-sell the Mastech unit as-is.
So if you're leery about buying from GoodLuckBuy, here's an alternative for you.
Note that I got my two from GoodLuckBuy with no worries, and they do sell both the true-RMS and non-true-RMS versions. So if you want to save a few dollars, go non-true-RMS.
SysComp does offer a bundle with a suitable RS-232 to USB adapter, which can be handy. There's no guarantee the MS8226 will work with all adapters.
The interesting bit, however, is their open-source logging software for the MS8226. Which is strange, since the Mastech instruments are hardly commonplace. Even weirder, they support a few other instruments. And weirdest of all, they support PC, Mac and Linux. (This is mostly by virtue of the Tcl/Tk scripting language they use, but still...)
As they cannot sell very much, it is a mystery to me how this is a going concern. They do have distribution, but it's all hobby-centric/retail outlets, which are hardly big volume.
Still, it's there, and may be a boon to those looking for an MS8226 alternative/replacement GUI. Reviews are generally positive, and they say they are available for personal support.
I haven't tried their MS8226 software yet, so I do not know if it is better than, equal to, or lesser than the stock Mastech software.
Specifically, I can't tell if it has a buffer limit or can save files to .csv format or not. There is no documentation that I can find. I don't like putting extra junk on my PCs anymore, so I'll have to wait until my current experiments are done so I can try the software on an older PC that I don't care about.