vaibhavp, I agree that the hd518 isn't too forgiving of bad recordings. They are quite detailed but at the same time they are fun to listen to regardless of being somewhat unforgiving. The one thing I find them to be forgiving at is with remasters. They have a dip at under 2khz that makes somewhat aggressive sounding remasters just right.
Listening to Depeche Mode remasters on the k518 is amazing. It feels as if the remasters were done using them as monitors :D