So I had this computer running Windows and then I put Debian 10 on it for testing. And now, I am putting Debian 9 on it. Because just as I wasn't prepared to have a valuable computer sitting there hardly being used for the few times I would need to run Windows, I can't have a valuable computer sitting there running a test version of Debian that other software can't run on. That computer is much more use to me as a secondary for mainpc or mediapc running some additional software when I need extra processing power for the other two Linux computers that are on my desktop.
Mostly this has been influenced by the fact I am not now involving myself very much in the development of Qgis as I was before. I am not developing the maps on a day to day basis using development editions of Qgis any more, I have switched back to using stable editions of the software, and this computer will run 2.14 to work around some 2.18 issues.
So if I run a development edition it will be possibly on mediapc but it will not be on any computer that has a screen at the lowest (eye) level on my desktop, except as a VM. To clarify that I have screens stacked three high, a total of seven screens, with two levels of three and one on the third level (that is mostly used as a TV). I haven't actually used any development editions for some time for anything at all, not since I was in Dunedin at Christmas and had a development master running on the computer I took with me down there. And as for beta editions of operating systems, they will have to run in a VM.