I bought CD-keys for StarCraft II (Wings of Liberty+Swarm) and they delivered very quickly. Little hic-up with the second key that was fixed by looking at the "SCAN" where a letter had been misread.
Trustworthiness really depends on who you're buying from on the site. The site itself delivers fairly well. If you're buying from a Marketplace seller, you can pay a bit shy of $2 extra for assurance of compensation from the site if the individual seller doesn't deliver. I've made a few purchases (from individual sellers), which came at steep discounts, and took only a few minutes to go through quite successfully. Marketplace sellers can be rated post-purchase, and those ratings are visible to all prospective buyers. So, despite my initial skepticism, I've actually been pleasantly surprised. The prices don't usually compete with official Steam sales, but when you don't have that, this is a great alternative, it seems like.
I had problems with CC charging/refunds. Order/payment gets "rejected" by their security system. Still my CC account was charged. G2A promised to refund (and said it was already refunded), but no money has ever arrived. My original order was almost two months ago...
Maybe the money arrives at some point. I don't know. However, I already contacted my CC provider and asked them to investigate/refund.
I can personally only recommend the g2a.com Service so far every game key i bought was delivered very fast and the only down part is that there is a User Marketplace where i bought some keys and they did not work but i got my money back in this cases ASAP so g2a.com is not to blame at all ! Very nice and fast live chat where they also take their time with you and stay with you!
Pas de soucis avec l'achat de clé-CD sur ce site, j'ai reçu mon contenu sous 10 minutes.
Je n'ai par contre pas encore testé leur mecanisme d'affiliation/parrainage, Ils n'ont pas l'air de beaucoup respecter la vie privée de ce coté-là...
Super boutique de clef cd. J'ai acheté "The guild 2 Renaissance". Pas de problème pour payer avec paypal et livraison de la clef immédiatement après paiement.
Je fais souvent mes achats de jeu sur ce genre de site et après 2 commandes sur g2a.com, je peux assurer que c'est celui qui livre les clefs le plus rapidement.
edit: j’éditerai sur les clefs viennent à être invalidées