http://unground6baopdio.onion/ :
As this site had not enough customers, we decided to switch it off. Thanks to all of you!!
More specifically, I think they shut down yesterday:
$ torify curl -I 'http://unground6baopdio.onion/'
HTTP/1.1 200 OK
Content-Type: text/html
Content-Length: 170
Connection: keep-alive
Vary: Accept-Encoding
Last-Modified: Tue, 26 Aug 2014 03:18:39 GMT
Accept-Ranges: bytes
Vary: Accept-Encoding
Expires: Wed, 27 Aug 2014 19:57:38 GMT
Server: TorHosting
X-Frame-Options: sameorigin
X-Frame-Options: SAMEORIGIN
X-Content-Type-Options: nosniff
X-XSS-Protection: 1; mode=block
UM was announced 4 months ago by /u/UndergroundAdmin.
My crawls indicate it never got any traction (my last one, 2014-08-24, showed ~5 active sellers with ~43 listings). The forum has been down for almost a month. It's unclear whether they took deposits with them, but I suppose only the 5 sellers would know. RIP UM.
I guess they were too undergound, nobody heard of them.
If they release an album, I'd buy it.