The part of me that like's getting expensive stuff for free is still indecisive at the impending deadline,
but the part of me that wasted the best part of a week trying to repair a brand new PC which was ruined by installing Win 10 is remaining very wary...

Even after reverting back to Win 8.1 and using the onboard Lenovo '1 click' rescue to mop up remaining problems,
it still has corrupt system files which Lenovo phone service technician says
"is probably the best I can expect due to compatibility problems
with the OEM system and registration key coded on the Bios chip
and Win 10".

I've about 6 windows devices that are eligible for Win 10,
and still wondering which ones to risk if I can find the time before it's too late to 'benefit' from the free 'upgrade'...???