I agree.
7000 series while still very relevant for gaming (especially on budget) have a serious problem: their model number is ... two years old? Maybe even three. Do not buy. Sell asap if you already have one as a new model will be out in a couple of months (actually sooner AFAIK, but availability is a big question).
7970 is exactly the same card as R9 280x. Probably the most widely used card for mining.
Their model number is still two years old. Explain this when trying to resell (albeit I would admit they're probably recognized as R something at driver level). Sticker is sticker.