One of the greatest features of Workstation is disk persistance for machine guests. It is unclear whether other virtualization offerings like Hyper-V, KVM, XEN, QEMU, etc offer the same robust guest disk persistance as VMWare. For me, it is a game changer. Once you have a guest virtual machine working the way you want it, consider setting said disk to nonpersistant. Nonpersistant disks are extremely useful. One scenario is setting the OS guest to nonpersistant and placing 'data' on another virtual disk that is persistant. Nice.
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