I've never bothered with "repair installs"
My personal motto has always been
"there is no backup like a cloned copy of an OS installation
on a spare hard drive"
(this is actually my second motto right after "Hard drives are cheap")
With this you can be back up and running in about as long as it takes you to locate a #2 phillips screwdriver to swap out your system drive.
I ALWAYS have a clone of my OS that is less than 7-10days old
(and favorites and settings are backed up seperately as well)
as for windows 8? I'm sure there will be a learning curve, but the other thing I see is that the prices on Windws 7 is already falling.
At this point I'll only buy Win7pro. because I've never yet paid $200 for a single OS installer...
But I'm nearly the poster child for "NOT an early adopter"