I am fine either way. If I understand the rules correctly, I will lose a slot (or perhaps two), meaning I can give away fewer games. But I have over 200 slots and try to give away 10 per week until I use up my extra keys. So I am fine there.

I believe the other consideration would be that if I had frequent "Not received" giveaways, I could get a knock on the door from the Admins. But the keys I have have predominantly been good (and I suspect some of the "the key was already used" I have received to have been fraudulent claims). I figure marking the key as not received means less work for the volunteer moderators and I am happy about that. So until I get the knock on the door, I am ok. :)