virt-manager needs to store Guest Image & Guest Settings in Home folder Like how VirtualBox does by default: /home/*username*/VirtualBox VMs Inside folder 'VirtualBox VMs' there is Guest Image and Guest Settings. This makes it easier for backup. Example, when upgrading to Fedora 18, I just backed up my Home Folder. Then if I need to use a Guest OS, I only need to copy the Guest OS folder from my backup into the "clean install" of Fedora 18. Then I just click Add Machine in VirtualBox manager ==> Machine ==> Add (CTRL + A) and point it to the .vbox file which has the Guest OS settings and also states that the .vdi image is located in same folder.
This really requires using qemu:///session, which we may never do by default, but we need to improve support for. *** This bug has been marked as a duplicate of bug 557103 ***
Why would I want to run a qemu session which I believe is a software only virtualization? Why not KVM? I really need to keep my virtual images on a separate hard-drive from OS.
qemu:///session uses KVM so you should see comparable speeds