In terms of being totally free, VirtualBox is better. Users will need to buy a Windows 10 Pro or higher license to run Hyper-V. However, with VirtualBox, you can run this on Windows 10 Home edition. The Hyper-V role installed on Windows 10 will arguably deliver better performance, since it is technically a Type 1 hypervisor and not a Type 2 hypervisor like VirtualBox. Windows 10 Hyper-V role virtual machines can be migrated from a client operating system like Windows 10 to the enterprise Hyper-V solution without any conversion. VirtualBox virtual machines will require conversion to move these around to different hypervisors. When considering running virtual machine Windows 10 environments that may need to be moved, this may be a requirement.