K240s are basically the same as the K242HD and the MKII, they're ~50€ on German ebay.
But beware, the velour pads are worth every cent. So if you snipe a set with pleather pads... spend some money on additional pads.
Oh yeah, back to topic. The K242HD are IMHO the better all-round cans, you'll hear the difference as soon as there is a person singing.
Plus, the K242HD aren't quite neutral (still far more neutral than the m50s) they pack quite a solid bass (a tad to much for me) and sparkle a bit in the highs.
Somewhat bath-tub style... which is quite popular atm...
Still, I like 'em and prefer the to most ~150€ cans around here.
But... both are great, the m50 is closed, the k242HD is semi-open.
If you plan on using it portable go for the m50s, else... throw a coin :P
Edited by roBernd - 4/10/11 at 11:44am