They market 3 items:
The software alone.
The software with the Teac Deck
The software with the Teac Deck and "secure" abilities.
The drive is the same drive in both packages. The final item includes full "secure" abilities:
"Secure models have the option of switching between Burst and Secure ripping modes (detection and recovery of errors)".
Secure models use both "Accurate Rip" and C2 pointers for error detection/correction. I own this model.
The "RipNAS" stuff is aimed at Windows Home Server users. The Deck/software package is setup to integrate into a WHS machine, and automatically rip the CD's and tag them for you when you insert them. The "secure" version even places "insecure" (read, "not verified as bit perfect") rips in a separate library folder. The deck is a finished "external" usb model; its not clear from the ebay page if the item there is a bare internal or a finished external model.
But in any case, if you don't have or want a WHS machine, buy the ebay deck on its own and their regular "dbpoweramp reference" software package (sold elsewhere on the dbpoweramp site as a standalone software package). This is not the "RipNAS" stuff.
You can then set the "dbpoweramp reference" software up on any PC with the TEAC deck installed and do the full "secure" ripping. The difference is that it won't automatically rip the CD, tag it, and place it in your music library for you when you insert it. You have to manually "tell" the software to do the rip (just as you would with any other ripping software), but if you set it up correctly, the end result will be the same as the deck they are selling in the "RipNAS secure" package.
BTW, they also market a ready made WHS PC with their software and the TEAC deck installed internally. Again, the RipNAS deck/software packages on their web site are designed for WHS machines. If you don't have a WHS machine you need to buy the "dbpoweramp reference" software and the TEAC deck separately. Go to the forum there for further info.