For you people in Europe that is going to purchase Diablo III RoS it might be worth considering buying it from the US Store instead of the EU one. I got it confirmed from a Game master that the keys are global which means they can be added on all regions and if you add the key to your account before the release date of the game, you will get the Wings of Valor.
- Go to Blizzard store.
- Change Region in the top right to Americas & Southeast Asia.
- Now you're able to gift it to your main battle.net account for $39.99 instead of 39.99 Euro.
- Add it to your battle net account.
Hope someone found this helpful