BigSky

Installation time of SP3 varies from user to user. For computers that rarely if ever get updated manually or otherwise, it will take longer because older files have to be overwritten by newer versions after the updater has cataloged a list of all system files to update, then it (updater) proceeds to update only the ones is has cataloged that need updating. The list will be larger, and the task of cataloging and updating will take longer if you haven't updated in 4 years. If you're like me, and update when updates come out, migrating from SP2 to SP3 shouldn't take all that long, because the majority of the SP3 installation is all the critical Windows Updates updates up to the point SP3 was released dating back to SP2, are included, as well as updated system files that not only Windows uses but Windows applications use. So, for me, installing SP3 took about 15-20 minutes (not including the 7-8 minutes it took to download on a reasonably fast cable modem connection)

Actually it is worth upgrading from SP2 to SP3. For example, if you haven't updated your computer since SP2 first came out, you've missed out on about 4 years worth of security fixes.

Right now I'm using Windows XP Home Edition with Service Pack 3, which I upgraded from Windows XP Home Edition with Service Pack 2 on CD that was bought retail in 2004 for about $99.