Dantz Development has released version 4.3 of both Retrospect and Retrospect Express, adding support for numerous USB and FireWire storage devices and erasing the 2 GB limit on file backup sets when used with Mac OS 9 or later on HFS Plus-formatted hard disks. In addition, Retrospect Express gains the capability to back up to a file on a secondary hard disk, something that was previously available only in the more-expensive Retrospect. (Keep in mind that a relying on single backup on an external hard disk isn’t an ideal backup strategy.) Upgrades for Retrospect users are available as a 14 MB free download (the Retrospect Client update is included); upgrades for Retrospect Express users cost $10 for a downloadable version or $20 for a CD with Mac OS 9.0.4 that can boot all current Macs. Both versions require a Mac running System 7 or later with at least 16 MB of RAM.