I forgot to mention, I did test the miniroot image on all the machines and it worked just fine.
I did a test installation to the USB yesterday and for some reason it was incredibly slow (ls takes about three seconds to finish as an example). I'm not sure what I missed. There was a boot message about firmware that I couldn't do anything about at the time but that shouldn't have /that/ much of an impact should it?
Other than that the initial test went fine, I'll probably get around to doing the UEFI part later today to see whether that part works as well, so far I don't foresee any troubles though.