Just a word of warning to give the opposite view. I've never had any problems with 100MB Zip disks, but I have had a 640MB CD-R become unreadable. Also I find that my HP CD-R goes through unreliable patches when all I can produce is a big pile of plastic drinks coasters. When it's working CD-R is wonderful, but when it goes wrong you can lose 640 MB instead of 100MB. Hopefully new machines are more reliable than the early one I got.