VMWare, VirtualBox, Xen, KVM, LXC and there are probably several other ways to run virtual machine under Linux.
Years ago I used first one. Then moved to VirtualBox and still use it. But when it comes to rest of list I do not have too much experience. Xen? One of my servers in past was Xen instance. KVM? Maybe used few times to quick boot some ISO image. LXC? never played with.
From time to time I look at tools I use and check for better replacements. When moved to Fedora I decided to try “virt-manager” to move from VirtualBox to QEMU/KVM. Failed. Tried again…
Today, after “playing” with virt-manager in Fedora/rawhide I decided to stay with VirtualBox for longer. It may have some issues but runs my WinXP and Linux instances without any extra problems.
Sorry to say but Virt-manager feels like a tool for its creators only. Error messages which could be in any random language, insisting on using /var/lib/libvirt/images/ for disk images (or do lot of clicks instead) and depending on so many software packages that it will probably take months before someone will finally fix it in rawhide.
And no, I do not want to go to running QEMU/KVM by hand. It is good for booting image to play with. But I need a way to add/remove USB devices in running system. In an easy way.
And yes, I know “report all bugs” mantra…