I'm currently going through the Win7/Win10 debate with myself at the moment, and I could do with some clarification of one or two of the points raised here. I haven't sold my soul to Microsoft out of any kind of religious belief - I'm currently using LinuxCNC for my router - but the new machine will use a CSMIO external motion controller for various technical reasons which aren't relevant here. However, that means Mach3 or Mach4 (I'm going Mach3, but again that's not relevant here) and that in turns means Windows. Obviously, I'm going to be free of any 32-bit parallel port issues, so it's Win7/64 (which I already have on my garage PC dual-booting with the LCNC system) or upgrade to Win10. I have heard two issues mentioned which seem to be particularly relevant.

1. Win10 will go off by itself and download and install upgrades. Is this true? What if you disconnect the network connection to the outside world? Will Win10 sit and sulk and refuse to play, or will it carry on running and defer any updates until the network reappears? Is this a way around the "it might stop and restart all by itself" problem for a machine running a router? I've only just (earlier today) upgraded my first PC, a laptop, to Win10 so I have no direct experience of this.

2. Win10 might install updates which either break existing software, are themselves broken and hence can disable the machine, or are incompatible with older hardware. Or hardware that Microsoft decides that it doesn't like any more, however you wish to look at it. My garage PC is one I rebuilt recently with a fairly new AMD-based motherboard and a cheap but big-name graphics card, which are probably the most relevant bits to become obsolete. However, they are new enough that it seems unlikely that this will happen within a reasonable estimate of the hardware lifetime anyway. Before retirement, I spent the best part of 40 years in the IT industry, and I am aware that big customers were paranoid about the possibility of their applications breaking after an OS or application software update. However, as a home user, I can't remember this happening. OK, a new OS might break an application, but that's not quite the same thing. If I ran a business that was critically dependent on 24/7 system availability, I might take a different view but as a home/hobby user, how likely is this to happen? As a small business, should I worry that much, or just keep my production machine isolated? One of the main reasons why I like to run the latest version of any OS and keep it updated is that my speciality used to be around IT security, and one general recommendation for any system connected to anywhere else was to keep it updated with at least security updates; the feeling was that as soon as a fix was published, someone was going to reverse engineer it to create exploit code, so you needed the fix to try to stay on top of things.

I look forward to comments for and against, but please, with reasoned arguments to support the position