Neil,

Check out the following site:
http://www.wtenaykeyboardstudios.com/drives.html

According to the website, Walt Tenay still carrys hard drives for technics keyboards and has comparison data set up really nice comparing the SX3 and SX6. He has always answered my emails and any questions I have. I do agree with Tony that the SX6 is better than the SX3. Technote's website is down for modifications, so I couldn't see if they still carry them.

Peter