We have been testing KVM inside our virtual servers for some time. Now we have enabled it for everyone.
From the beginning, vpsFree.cz has used OpenVZ container virtualization. But users have long asked about running their own Linux kernel or another operating system. So some time ago, we started experimenting with KVM.
All members can now enable KVM through vpsAdmin. KVM joins the other VPS features (such as iptables and TUN/TAP) configurable in the VPS details. Just enable the new feature. The system will restart, and the KVM kernel interface will become available inside it.
This means you can create virtual machines with KVM inside your VPS (an OpenVZ container), using libvirt, for example, and run any kernel version or even another operating system.
Exactly how to use KVM with libvirt is described in the knowledge base. We would be glad to hear about your experience, especially what you are running in KVM.