What are some alternatives?
When comparing virt-manager and Parallels, you can also consider the following products
VirtualBox - VirtualBox is a powerful x86 and AMD64/Intel64 virtualization product for enterprise as well as...
oVirt - oVirt is a virtualization management application.
VMware Fusion - Simple and powerful virtual machine for Mac. Mac virtualization software. Learn more about VMware Fusion and try it free today.
QEMU - QEMU (short for "Quick EMUlator") is a free and open-source hosted hypervisor that...
VMware Workstation - VMware Workstation is a multiple operating system handler to easily evaluate the any other type of new operating systems.
Proxmox Virtual Environment - Proxmox VE is an open-source server virtualization platform to manage KVM virtual machines, LXC, software-defined storage and networking, HA clustering, and multiple other out-of-the-box tools on a single solution.