Also have Cablevision/Optimum - Just adding as I know people have been looking at drive options.
Well, tried the WD My Book expander initially, which stopped working after 6 months and had other issues. Example: I could only get the SA8300HD to recognize the My Book by powering the My Book on after the SA8300HD had booted.
I then tried a few years old AMS Venus I had lying around. NOTE: This caused the SA8300HD to continually reboot and perform diagnostics (hex countdown). The USB/esata enclosure interface also looks to have burned out.
Eventually ended up with the Vantec, which I didn't initially realize had been posted here (Vantec NexStar 3 3.5" SATA to USB 2.0 & eSATA External Hard Drive Enclosure (Onyx Black) - Model NST-360SU-BK)
I also used the following disk (also from newegg).
Western Digital Caviar Blue WD10EALX 1TB 7200 RPM SATA 6.0Gb/s 3.5" Internal Hard Drive -Bare Drive, which was $65.
For this combo, the reboot was completely smooth. Powered on drive, powered on SA8300HD. When I turned the TV on, the format screen was already displayed, no hesitation or hangs. It has only been a week, but no issues so far. I do leave the external drive powered on.