ignatzatsonic, some of what you ave saying depends on what copy of Windows you have. If it is OEM, it will be tied to the same hardware that you have when provided the Windows 10 key. Retail would not have this limitation, so long as it is one install at a time.
Once you have the key, you are golden......you can go back to what you had, stay on 10. Point is that a key for 10 "should" last you quite a while.
As I said in my post, I'm referring purely to a RETAIL Win 7 installation, that is then upgraded by the free upgrade offer before next July. Then you immediately revert to Win 7. Then in 2018 you buy new hardware and attempt to get Win 10 on the new hardware without paying.
You don't get a new key as far as I have heard, with the free upgrade offer.
"Should" doesn't inspire me very much. That's the problem.
I realize there is no issue going from retail 7 to Win 10 now or until next July. I'm referring to 3 years down the road, coming from Win 7, after you've already upgraded to 10 and then reverted to 7.
We need more info from MS and no one is likely to believe what they are told until AFTER the free upgrade offer expires and people start experimenting.
I don't mind paying in 2018 in that situation. I'm just wondering if I'll have to. Win 10 has nothing I need, but like everyone else, I will be forced off Win 7 sooner or later.