..and I bet you are an authorized M$ reseller or refurbisher?
Personally I quit installing from DVD a long time ago. I now do it via USB and most of my images are created using some sort of update integration tool - rt7Lite for windows 7 images, etc.. Yes it takes a little longer this way, but I have no problem with that. And since we aren't super busy (haven't been for years) and I only work part-time.....well I think you catch my drift.
I did work on 3 Okidata 9-pin printers this morning - just needed cleaning and lubrication as most do from this client. Oh and needed a print head but those are super easy to replace!