Re: "the time it takes to bloat over all the drive it was installed on"
Your VM can't grow the drive size to something adequate? Sounds like a software problem to me.
While it is true that when Bill Gates uttered the infamous phrase that disk space was free it wasn't, these days is pretty much is. Even a cheap laptop comes with a 250G hard drive these days, and even at 81G for all of my installed apps and data on my work system, that's not even 1/3 of the available disk space.
True, you'll probably have problems with .dll rot and the like, but with MS shunning service packs, these days you'll get that no matter what.