I have recently bought a 24x drive for my Umax S900. It was advertised as a Cyberdrive, though it doesn't say so anywhere on the drive itself, and it is sold very cheaply here in Germany (about 15$). Soon I realized that it wasn't worth even those 15$, because it was really slow. It took up to a minute to read the directory of a CD, and rotation of the CD kept slowing down and accelerating alternately. I assume this was due to read errors, but the CDs worked fine in other drives. Maybe I just had bad luck, but the low price compared to other SCSI drives doesn't make me think so. I have never tried if it is possible to boot from the drive, though.
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