@Targhan
I'm sure it could be changed, but when those settings are changed, it is universal (AFAIK). This is for the Mass Storage Device in Poseidon, and would likely hold true for real os3.x Amigas as well. I don't think it is a bug in Posiedon either, but a choice that had to be made. To my understanding regular (IDE or SCSI) zip drives should work on a Pegasos with MorphOS as they would under a native Amiga.
I
think you should be able to configure the device seperately and those settings are only for that device. In other words, configuring the class is universal while configuring the device is not.
(Haven't tried it as the two devices I use need to be accessed on both my PC and Peg.)