VirtualBox is ridiculously simple to set up and get virtual machines going. Shared folders, shared clipboard and much more are no issue.
But.
It eats resources. The installed virtual machines (VM) run relatively slow. What have you found to be feature comparable - and most importantly more resource-efficient - alternatives for running VMs under Linux?
I haven’t used it nearly as much as VirtualBox but Boxes (flatpak) is definitely a breeze to use. It uses KVM under the hood I think. If your use cases are complicated it might abstract away too much though.