This was in 2007-2008. I've only played one game since then with them, and that was last week against Tyranids. Destroyed the entire fleet while taking only a single point of damage in return, but then he was relatively new.
My only loss was against FW Tau because of the scenario; I lost all my ordnance capabilities on the first turn, so had no defense against his masses. Otherwise, have defeated all-NC IN, two SM (one was all SC), one Eldar, and one Orks.