Have I been asleep, or is THIS a new development?
Matte silver inkjet printables have been for sale here for a while afaik.
edit: ah, I see what you mean now. Not sure if the silver ones here that I saw allow printing including the hub. The white ones do.
At least the ones at xmediatrade seem not to:
Both claim full surface printable, but not the hub.
Do you have pictures of the discs from that store you link to?
AFAIK, this is the 1st hub-printable silver ever. Silver printable is actually a clear coating over plain silver discs. The hub area does not have the silver reflective layer, and so should be more or less opaque. I’m curious to see how they look.