You should be fine - only cavet is must use same version ie win 7 64 bit pro. Using a disk that is same version but is the upgrade (verse oem and full) is no problem.
You need to select "custom" for the install and do a clean install DO NOT INSERT KEY at this time.
Once the clean install is completed, you can let windows do it's update thing and load the needed drivers.
Everthing looks good, then just need two steps:
Edit the registry to change MediaBootInstall from a 1 to a 0.
Then run a cmd prompt (w/admin privliage) and do a rearm
Then Activate and insert the LAPTOP key.
Wiil post link
Yes, Ive Have used this method on my new SB notebook. Used a upgrade windows disk to install windows (instead of the supplied disk) and used the laptop key, NOT the key on disk.
Here is the Link, Go to method2 - Use search function to find MediaBootInstall, simpler than keep scrolling down that LONG #@#$ list.
Can I just ask? If I remove that ei.cfg file from Windows DVD and burn it on another one, would that not make it clue-less of what version it is I am installing? I will try both methods and see which works easier.