Parallels can have trouble installing or importing Apple's server in a virtual machine, and VirtualBox just doesn't support it. If you want to run Mac OS X Server in a virtual machine, however, VMware Fusion 3 is the clear choice, providing the most trouble-free and solid experience. Both are far more advanced than VirtualBox's Seamless mode. Both do a good job of hiding the Windows desktop and integrating Windows applications in the Dock, Expose, and Spaces. On interface and Mac OS X integration issues, the merits of Parallels and VMware are more subjective. Not that VMware Fusion 3 is slow, but it can stumble with graphics-heavy tasks and uses more of the Mac's processor, leaving less CPU bandwidth for Mac applications. Parallels Desktop 5 provides the best overall performance.
Furthermore, these new versions add support for Windows 7 Aero features, such as Aero Peek and Aero Glass. YES, you can run Mac OS X Sierra on Virtualbox installed on Windows 10 for. Parallels Desktop 5 and VMware Fusion 3 also automate the installation of guest operating systems and support multiple monitors. Since 2006, Oracle Linux has been completely free to download and use. VirtualBox has a few unique features and is free, but doesn't support many Mac OS X features. VMware Fusion 3 is a close second, with Sun's VirtualBox 3.1 running a distant third. Overall, Parallels Desktop 5 for Mac is the top virtualizer for Mac OS X.
