Having been running Windows 10 on my PC for several months now I can safely say that anyone that sticks with 7/8 is just in fear of change. Win 10 has so many improvements from both 7/8(8 had many improvements over 7 but too many poor UI changes)
The OS runs smooth, my PC has suffered less crashes since switching from 7 to 10.
Currently on Build 10041.
Windows 10 is 'free' forever. There is no subscription model. The only way that a subscription model would come in is if they introduced it and you decide to buy it. As it stands it works the same way as every windows version beforehand.
The 1 year is a one year period that you can avail of the upgrade.
@reggin_bolas If you are able to run Windows to download and install this then it should fix whatever problem you are having. However if you are unable to run windows you won't be able to access the reserve page. You may need to upgrade from a disc/usb drive. Installing an OS works from the boot menu so if your current version of Windows doesn't work, it won't effect you installing or reinstalling a new version of Windows. I use this technique to 'fix' computers all the time