version recommendation for VGA passthrough in Windows 7guest, on headless host

I plan to setup a headless KVM hypervisor (i.e. pci-stub assigned to GPU) and guest Windows 7 with vga passthrough to AMD GPU as the only screen (i.e. -vga none -device vfio-pci,*). I have SuperMicro motherboard and a pair of Xeons E5-26*V2 and plenty of RAM for this, and am not afraid of running bleeding edge version, if it helps to make such setup perform well. As for distribution, I consider starting with Arch (thanks to this guide https://bbs.archlinux.org/viewtopic.php?id=162768 ) but Fedora 20 or other options are obviously open.

I am looking for recommendation where to get most the fitting package or sources for the task, for libvirt and qemu (and what else?). My starting point will be likely kernel 3.13.4 , libvirt 1.2.1 and qemu 1.7.0 . Should I look into git repositories for development versions instead, or any specific patches? Where from? TIA!

B.