Clone cd and cdrwin
 

I dumped a psx cd with both of these, and there's a 1000 byte difference in the image size. Surely they'd be the same?, or have i got it all wrong...
cdrwin38c and clonecd 30011

Its down to the way in which the software reads the information or to be more exact what information is read. CDClone will read the protection where CDRWin wont and this probably accounts for most of the difference in the file image sizes.

If you tried 10 different types of software to image the same file you would probably get 10 different image file sizes but after burning the end result would be the same!