I'd love to hear your impressions also. I'm still deciding whether I should order my amp as soon as Dan gets them in stock, or if I should wait until after Christmas (might be easier on mah pocket book).
I'm not a big fan of the AKG k240, to be honest. My school's studio has maybe 15 pairs of them, and a lot are falling apart, often around the ear cups and the plugs get to the point they have wires showing. They don't sound very rich to my ears, but then again, they're fed through group headphone amps with quality out the window. Also, I'm not sure whether they are classified as sealed or "semi-open", but they don't block nearly as much sound as they should for recording purposes. A lot of the musicians complain about how they feel, and the singer I was recording tonight said it was squeezing the her face by her ears and making it hard for her to sing. I think for junk studio headphones, there are better choices. I hadn't really considered them for detailed listening.
Oh, speaking of the studio, I have brought my headphones to sessions with three different clients, as they seem to provide a more accurate picture than the studio monitors do (the 3k pair have too much warm mid range and the 11k pair are way too hyped). And out of the three clients, two of them would walk in after a take to audition and immediately put on my headphones because they considered them to be the best listening source. It makes me proud of them.