Besides this you get also discounts on all products on ares-shop.de .
For example games which cost normally 30€ will cost 25 and some are even 6€ less expansive. On top you get 3% on every purchase on ares-shop.de
You can exchange credits also to indieCoins which can be used in the indieGO! Appstore.
Besides games and apps you can also get Hardware like the Raspberry Pi, indieGO!, Odroids and other systems.
So basically you save two times..