What may be news to you, however, is that you can easily extend the 30-day Windows Vista grace period to 120 days. No hacks required. This is an official, supported operation directly from Microsoft.
With the amount of testing I do, I'd say this was a good enough period for a test, wiping out the drive, and reinstalling and testing again. I think the version of Vista downloaded from MSDN has something like 10 activiations, and I must have already done at least five if not more. This should help a lot.