I live in a mobile home so speakers have never been an option, permanently attached to my head they have been for the past twenty odd years. Going from cheap rubbish hanging on a rack in Argos to Grado SR80's and hearing what real headphones sound like was a revelation. Senn 600's, AKG 701's, Ultrasone 2500's, Grado HF-1's and now K712's.
Would still have them all but I tend to lounge around in bed wearing them and they break. Still have the last three, although my AKG's are messing up at the moment. Keep the Grado's for special occasions - Sigur Rós marathons, hate the short cable, lovely and thick except the point where they twist and get kinks in.