When comparing VirtualBox vs VMWare Fusion, the Slant community recommends VMWare Fusion for most people. In the question“What is the best VM applications for Mac?” VMWare Fusion is ranked 1st while VirtualBox is ranked 2nd.
Ranked in these QuestionsQuestion Ranking
Pro Free and mostly open source
VirtualBox is available for free with source code available here. A "VirtualBox Extension Pack" that includes virtual USB 2.0, VirtualBox RDP & PXE boot support is available only under a commercial license.
Pro Fast, reliable, flexible
Pro Seamless or Isolated Modes
These modes are fantastic and allow the user to choose what kind of environment the operating system runs in.
Pro Lots of administrative features
VMWare Fusion supports accessible network devices, limiting USB device connectivity, adjusting memory configuration and encryption of VMs.
Pro Can create powerful Virtual Machines
VMWare Fusion can create VMs with up to 16 CPUs, 10 network adapters, 8TB disks, and 64GB of RAM.
Pro Performance comparable to Parallels
VMWare Fusion has the best-in-class multi-core performance and trails slightly to Parallels in single-core and memory tests.
Con Inferior performance
Apart from second-class performance in virtualization, there are some visual glitches with Windows 8.1 on Mavericks.
Con Confusing interface and lacking usability features
VirtualBox might be a bit confusing for beginners - it requires an understanding of a lot more technical details than other VMs.
Con Performance comparable to Parallels
Con It's not free
VMware Fusion is a proprietary software that costs $79.99, although it is very good.
Con Gaming performance is lacking
VMWare Fusion's gaming performance is slightly below that of Parallels Desktop.