I am going to have to bite the bullet and upgrade my OS soon. I have been running X1 and X2 with Vista 64 with out any issues. Some of you guys may have seen this thread upstairs; I loaded X3 on my machine and it ran great, but can not access any of the new VST's that shipped with X3. I own Melodyne Essentials already, but have not being able to scan my version with the X3 VST Scanner, seems to block Melodyne from running in the ARA mode. I swapped out the VST Scanner from X2 to X3 and then it scanned my plugs. Both Seth and Noel were all over it, had me fill out a report and they would like to see if they can make it run from Vista. I thought that was a really stand up position for the guys to take when it is clearly stated that Vista is not supported. There is apparently some sort of hand shake that happens with the new VST Scanner the unlocks the new includes software and Tape Sim, along with opening up the ability for Melodyne to work as its supposed to with X3.
I have a copy of W8 upgrade sitting on a shelf. I have been really reluctant to wipe my machine clean and do a clean install of W8. Not only because its a lot of work, but also because I really don't like the new way it interfaces. My son got a Toshiba lap top with W8 before running off to Texas Tech this fall and we were both really lost on W8. I guess, I am seriously thinking about buying an upgrade copy of W7 and going that route. I am just waiting for the family to decide to take a trip to Grandma's and leave me an entire weekend to sort it all out.
In the mean time, I am still using X3 to produce music. I imported a song I am 95% done with from X2 into X3 and everything runs even better than before. I have already used the comping features and love them. I also love the fly out EQ. No crashes what so ever.