Wolfie,
There is no such thing as a standalone HDTV DVR, because the technology isn't yet available to affordably record from DVI / component. As a result, all HDTV DVRs will either have a HDTV STB and DVR integrated into the same box, or they'll rely on Firewire (which no Sony STBs have) to connect STB and DVR. This is not likely to change in the next five years.