I haven't found a definitive recommendation from Microsoft one way or the other. All I can say is that I've repeated Sysprep on a disk image myself, and I don't recall suffering any wrath as a result. The only issue I know about for sure is that after a certain number of runs, Sysprep will no longer reset the product activation grace period. I didn't find any description on Microsoft's Web site of the exact number of times you can run Sysprep before it stops resetting the grace period, though.
Related Q&A from Jerry Honeycutt
Have a question for an expert?
Please add a title for your question
Get answers from a TechTarget expert on whatever's puzzling you.