I bought Parallels back when it first came out. I was new to the mac and needed to transfer my windows skills but also needed a safe place where i could keep my essential windows apps. I wondered had i made the right choice so tried copies of all the other windows virtualisation software on the market. We are now on the 15th release which is a major rewrite, and provides the mac with a slew of utilities i mostly don't use, the reason is i had already bought into individual solutions form other suppliers. As time passes i find that i am switching to the parallels utils as a cheaper option when upgrade time comes along for the individual apps.I still use windows XP for some apps and i still use mac mountain lion for others. To me, why throw away a really good utility just because the OS doesn't support it? just keep the old OS and the utility.