I have an A3000 with external SCSI Magneto-Optical Rewritable Removeable Media drive since circa 1990 and I have turned the external drive off/on with or without the Amiga being on 74 GAZILLION times and never had any problem whatsoever.
Back in the 1990's my A3000 was on 24 hours a day and I just turned off/on the external drive as needed (about 20 times per day).
A3000 SCSI RULEZ 4-EVA :-)
P.S. Do NOT turn the drive off in the middle of a write operation. :-D
