I ran my Tivo HD for years like that. I had an eSATA RAID enclosure attached to the internal drive connector of the Tivo, and just ran a "single disk" Tivo that happened to be running on RAID. I simply did it for protection against a drive failure and losing my recordings, though that is not how it started. I was originally testing when Spike was working with "large" volumes and breaking the 1TB barrier. The enclosure had five 1TB drives in it as RAID 5, though I was ultimately not able to use anywhere near that. To get it to work, I ended up having to carve a volume of 1.26TB out of the RAID. Anything larger than that would not work. That was as large as it got until solutions like JMFS came along, and ultimately the series 3 "k" software version that allowed up to 2TB.