I have a Epson Perfection 4490 with no 64bit drivers. I will need to either run Windows or a older version of Mac OS / OS X. I'm sure there are other use cases where one will need a older system. I was actually going to go down the route or building a new Hackintosh but have opted o build a Linux desktop with Mac OS VM using GPU pass through. Using this I could have the latest Mac OS and a older version when needed.