QEMU vs Virtual Box
When comparing QEMU vs Virtual Box, the Slant community recommends QEMU for most people. In the question“What are the best desktop virtualization solutions?” QEMU is ranked 1st while Virtual Box is ranked 3rd.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Near-native performance
Pro Free and open source
QEMU is available for free with source code available here.
Pro Can do snapshots
QEMU is capable of taking whole-system snapshots and writing them to a backing file.
Pro Compatible with Many Operating Systems
It works for Windows, macOS, Linux, BSD, and many others.
Pro Beginner friendly
A virtual machine can be set up in minutes if a ISO file to load is already available.
Pro Works well and fast for Windows host and Linux guest
Pro Free and open source
Pro Many free images available
Though most are linux flavors at https://virtualboxes.org/
Oracle's virtualbox site has others.
Pro Can do snapshots
Pro A lot of customization
VirtualBox has multiple virtualization options. Each one may be tailored to the guest operating system’s needs. This makes it especially good on virtualizing older systems, such as DOS, obscure distros, etc.
Cons
Con No official GUI
Con Lacks video performance
Virtualbox has a hard cap of 256MB of video memory. This could make newer operating systems run slower.
Con Minimal CPU customization
You can only enable/disable certain features. You cannot cap the speed of the CPU, which is required to run systems such as Windows 95.