What should I compare in authorized game key stores?
Start with what you actually receive, not just the price. Xbox, a publisher store run by Microsoft Corporation, sells game keys, gift cards, wallet codes, game subscriptions, in-game currency and DLC, and delivery is instant. Its monthly subscription is $9.99, with a free trial of 14 days and a catalogue of 50 to 500 games. Read the Xbox review for the full picture.