Welp, we've been wrestling with the HD storage issue for several days now, and there is no consensus over what storage solution is "best" for long-term/high capacity/ archival storage of HD material.
I've been using RH-10 (some Hong-Kong mfg's model number for these generic removable bays, widely available through local computer shows, screwdriver shops, and geek/gadget websites) type removable drive bays for about 4 years now, with no issues. I power down the system before pulling the drive out and putting in another. If you set your mobo BIOS to "Auto detect" the hard drives, you can swap out a 20Gb for a 45GB or 80GB, and the motherboard will auto-set the drive parameters. Assuming you swap only one drive at a time, the drive letter will remain the same- it's as if you are simply changing floppy disks!
Win98SE probably handles hot swapping hard drives (fully powered up on the Win desktop) better than Win95 did. I still power down my system to be safe, as munging the FAT32X table on a filled 60GB+ hard drive is not a cool thing to do. There are ~$80-$100 hot-swap certified hard disk drive bays out there, which probably require the installation of included driver software to ensure safe hot-swaps, but I still would power down my system with them anyways. Therefore, I stick with the low cost generic swap bays, as they perform just as well if you don't want to hot-swap.
I have done the following recently with external SCSI hard disks (old 2GB-10GB drives lying around): power down an external drive attached to a 2940UW card; detach drive from external SCSI cable; re-attach another SCSI HD; power up new drive; Right click My Computer => Properties => Device manager => Refresh. The new drive will come up fine, as if connected at powerup!
If a new drive letter is needed, it is automatically assigned the next available letter.
The latest RH-10 swap bays I've gotten acually have the drive power routed through the drive cartridge locking switch (the keylock that locks the drive cartridge to the drive bay holder, the part that stays in the computer). So, when you turn the switch with the included key, the IDE drive is powered down. I'm assuming that using the procedure above with the SCSI hard drives, an IDE drive would probably come up fine as well if I replaced it in the bay with the latest power-switched RH-10's. I haven't tested it yet- maybe the BIOS needs to be informed of the swap for IDE drives (?). The driver software that comes with the expensive hot-swap bays probably just automate the file-closing/Refresh procedure.
Any other users of hot-swap bays out there? Opinions on brands/problems/etc?
Yes, my initials Really Are R-G-B!