It would seem that 4 members of the Finnish guild Aquila have been able to complete the achievement Challenge Conqueror: Gold.
As a side note I am looking to get in contact with any of them to look to form a nice feature for the front page, so if anyone can help me get in contact that might be cookies. Edit: Contact made! Expect awesomeness interview!
http://i.imgur.com/bdaUI.jpg // http://i.imgur.com/rtEWx.jpg
Razoki (Rogue) [Armory / Wowprogress]
Taki (Shadow Priest) [Armory / Wowprogress]
Rathy (Blood DK Tank) [Armory / Wowprogress]
Decev (Frost DK DPS) [Armory / Wowprogress]
Deloop (Ele Shaman) [Armory / Wowprogress]
Reddit thread