I don't know anyone who's done it (it's still a bit too expensive for me to give it a shot) but it appears to be a fairly standard saliva sample kit that you mail in.
Yes compared to HDD it's way too expensive to read. However tape backups are also cumbersome and time-consuming to use, but the fact that you can get extremely cheap bulk storage from them means lots of big companies still use them. So I could see it maybe being competitive there (eventually).
Illumina appear to be targeting 100USD right now. I think their markup on reagents is probably at least x10...
But even that’s super expensive compared to reading data from a HD... so you have to wonder where DNA as storage is viable. Unless a vastly cheaper read method becomes available.