gibbeynator: Except Green Man Gaming, they're good. CDPR would like you to THINK they're "EVIL ILLEGAL KEY THIEVES!" though, but they're not.
Darvond: Did you even
read the specific phrasing I used?
It doesn't matter what your opinion is, if CDPR doesn't actually sell direct or authorize them, then you can't trust the key received as genuine, even if it is valid.
Sure you can. The fundamental problem with G2A is that a lot of their keys come from fraudulent transactions- stolen credit cards usually- so the original seller reverses the transaction and the key you bought gets nuked; and G2A aren't good at or don't care about vetting such transactions.
CDPR doesn't have GMG as an authorised reseller but so long as they buy their keys legitimately and re-sell them once then the keys are perfectly safe to buy, and CDPR even gets money from the initial sale. That model has been used extensively and perfectly safely in places with ludicrous regional pricing models such as Aus/NZ for years- nz/ausgameshop sells keys usually from UK or eastern Europe boxed copies, you can even have the box shipped out unopened if you want; and cdwow (renamed now and I can't remember what to) sells copies from boxed asian copies. So long as the site is honest it's safe.
The problem with G2A is that they fundamentally aren't honest; they definitely don't buy the keys themselves and there may be multiple grey market sites all selling the same key, which was bought with a stolen Visa and will be cancelled in x days time. G2A has an awful reputation while GMG has a good reputation, and each for good reason.