That sounds fishy to me as well. The eject command is electrically the same on the 400 and 800k drives, and I likewise know that my 64k ROM 512K will eject the disk before rebooting if booted from an M0106. I can't boot with my particular M0131 because it has the earlier 800k mechanism that triggers the divide-by-zero Sad Mac bug in the 64k ROM. But if you have one with the later 800k mechanism that basically adds "noise" to the TACH line it should behave like an M0106.