Never used go back..
Ghost is very useful, as J273 says, backing up your initial pc setup so you have something to fall back on.
I use Ghost most days at work..
was well glad of multicast ghosting, when upgrading all of our 70+ sites that had hundreds of pc's to be re-imaged! it did a very good job & didn't have any real issues, except when users decide to switch pc's on while they are waiting for the session to start, which buggers the whole lot up!
At the moment i'm mainly using it with a crossover cable to re-image single pc's from a laptop when out on sites if needed.