No one gives a rat's ass about Microsoft TOS, keys will work forever.
No doubt they work but you shouldn't steal them and if you disclose that too, you wont be getting any buyers. There are many sellers here and those legit ones like Floord-1 and myself also. Who would like to buy stolen ones and not go to those who offer fast and scam-less service ??
Because I sell cheaper, who cares how I got them? If they stop working which will never happen I'll give them another key.