On the fly can be performed reliably by very few combinations of devices, examples are:

Tosh & Acer
Tosh & Plex
Tosh & Lite-On

Gee, did I say Tosh three times? There are others & I would be interested to hear of members experiences with some 'unusual' or less sexy combinations.

Of course, try it with Laserlock or LockBloks & you're asking for a coaster christmas tree.

You've gotta have fast HDDs like SCSI or, at a minimum, ATA66, busmaster drivers (preferably MS if you have a VIA chip**) installed & DMA enabled. Reader & writer must be on separate channels or best, one device on a separate controller.

For CD to HDD to CD-R, defrag your HDD & set the swapfile to a managed permanent size, like 200-400 MB (mine is 250 MB with 512 MB of RAM). Dedicate a partition or drive as the "image" container e.g. mine is a 30 GB d;\images and nothing else (good for D-Tools too!)

**VIA claim to have fixed their busmastering issue with the latest 4in1