@A4000_Mad
You will be able to just buy a new bigger drive if needed. I have Seagate Cheetah 73 GB 68 pins drives connected to a CSPPC and a CSMKII, as well as Seagate Savvio 2.5" 80 pins drives connected to a Blizzard PPC and WarpEngine 4040.
Most drives will work; I'm quite happy with the Savvio disks; using a 80 --> 68 pins adapter (it's needed for connecting the drive, so no way around it), a mounting rail from 2.5" form factor to 3.5" form factor and you have a low noise SCSI harddrive, and better airflow in a desktop cabinet :-)
I'm using ACard IDE adapters as well, from 50 pins as well as 68 pins. They are a wonderful invention, and working great, so highly recommended. Nice to know that the 2.5" notebook adapter a-pex have can also be used.
-EDIT-
I have some spare drives if you can't manage to find any. They are from 1 GB to 74 GB, all working, but some are louder than others.