I purchased the Western Digital 500GB My DVR Expander eSATA External Hard Drive yesterday and connected it today to my Scientific Atlanta 8300-Series DVR (from Time Warner). Worked like a charm. Don't get me wrong, the Scientific Atlanta 8300 is a piece of garbage compared to a TiVo. But I went from 65% full to 15% full, a 4.3x increase if my math is right. Woohoo! I can finally let the DVR record niche shows I like to watch occasionally like Colbert Report and Deadliest Catch.
I paid 150 clams for this privilege, though, $50-$70 more than what a 500GB eSATA HDD should cost. Ouch. However, when I researched expanding my DVR, it seemed that there wasn't consensus on whether any ol' eSATA HDD works on my DVR model. I really didn't want to have to buy a HDD that I'd have to return, so I waited until dealnews stumbled on a deal for this model, which is intended for DVRs. I might have pissed away $70, but I might have saved myself lots of time and trouble. Any brave souls out there that have gotten any ol' eSATA to work?
And may I add ... OMG, I picked budget shipping from Buy.com, and I got this item next-day. WOW.