I have the AKG K240 headphones, they cost about $90 at guitar center locally. They have a really flat sound and they are not too biased on either side of the sound spectrum. THe only thing about these is they are 600 ohms, so you will need a lot of power to drive it. The Grado's are good, but I've heard stories about them breaking after a year or so. The AKG lasts 10+ years.
As far as Sony goes, get the sony v6's, and not the 600's.. the v6's simply sound better. Hope this helps .