Thanks for that John.
I did take the precaution of running the 'verify' procedure after creating one of the images, thinking that the programme would have a quick look at the file, declare it wholesome, or otherwise, and then let me get on with whatever it was I was doing.
But not a bit of it! Verify takes just as long as the image making itself - although I was pleased to see that DiscWizard did declare its own work to be sound.

I'm pleased I have the images, but I can only see myself mounting them if everything has gone south. My 'users' (who operate very strictly on an 'if it ain't broke - don't fix it' principle) would not understand it if I broke what is currently a fully operational system.

Anyway, I'm much reassured by your testing and by your own faith in ATI!

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