External Disk – Improve Read and Write Speed for Mercury Elite Pro Dual Mini

Option 1: Mount drive read-only

You can mount the USB drive read-only by using Diskutil.

• First, insert/mount the drive once, run diskutil list from Terminal.app and take note of the device representing the drive (should be something like /dev/diskN with N being any number).
• Eject the disk by running diskutil unmountDisk /dev/diskN replacing N by the number noted in the first step
• Mount the disk read-only by running diskutil mountDisk readOnly /dev/diskN

This of course requires that you actively run these commands every time you want to use the archive stick. For an automated solution, have a look at MarcoPolo or write a launchd command (see e.g. here for inspiration).

Option 2: Use access control on the drive

Does the drive really need to be formatted in FAT32 or do you only access it from a Mac OSX system anyway? In the later case, you can save the drive content on another drive, reformat it as a Mac OSX drive, move/copy the content back and take away any write rights from anybody.

Although that enclosure accepts 12.5mm drives, those WD Passports have the USB connector built into the drive. They don't have a standard SATA connector and therefore cannot be used in that enclosure.