I had a democar from my dealer for a few days during this summer, and I heard the suspension clunk when driving on bumpy gravel roads or when I "accidentally" hit a hole in the road. When driving normal on ordinary roads, nothing could be heard.
Of course, I'm sure everyone have handled the loaner pretty hard.... I'm sure I did
BTW: The loaner had Dynamic Damper Control. I'm still waiting for my 2012 (March) with DDC and hope this is not an issue with DDC.