Is that WOW US keys for 4 euros ? I don't think so ? Also had problem with onlinekeystore, took them 2 days to deliver a US Vanilla key, which didn't work. I didnt bother and just google charged back.
onlinekeystore charge me back aswell.. full details here http://www.buddyforum.de/showthread.php?2935-Don-t-Buy-Gamecards-from-onlinekeystore.com&p=31063