This mostly seems to confirm the old addage that linux is only free if your time is worthless to be quite honest. How much performance do you tangibly lose if you just use a windows box that works to whatever extent it works, but reliably so?
However, that is untrue. For the slow kids who have trouble using Linux, or using it without a windowing system, the time they lose would surely be made up during CHKDSK, waiting for Windows to boot, reinstalling software, reinstalling the entire OS when the registry is trashed, or reinstalling from whatever else is certain to go wrong.
Anyway, the amount of time it takes to install, update, and manage even a small cluster of Linux boxes is miniscule compared to the same task with Windows. You don't need some fancy ghost imaging software, sysprep, or waiting to do manual installs. You just PxE boot everyone off of a single image, or dd a single image onto each machine and you're running when you finish your beer. Sure, you can mostly do that with Windows, but it's not going to be free and neither is all of the time it will take.
Setting up a single machine takes the same things it takes on a Windows machine: drivers, ATI Stream SDK, and a miner. You don't even need AMDOverdriveCtrl or RadeonVolt.