Since there are a lot of technical guys around here, this might be interesting for you...
I've found download links to Windows 7 disk images with integrated SP1 on the Digital River servers. Digital River runs Microsoft's download store, and these are the links they provide when you purchase Win 7 online.
However, the links also work without purchase. Without a legit product key they're quite useless of course. I've collected all the links on my website:
The advantage of installing with an SP1 integrated disk would be to avoid blocking the computer with Windows Update for hours and hours.
(Hope this doesn't violate the forum rules, but as the download links are also regularly posted on the Microsoft Communities, it's definitely not pirated stuff.)