It really depends on what music you like. For me, my favorite by far under $100 (and even $200) is the Koss Pro DJ 100.
They have some of the best vocals i've heard and are good for most everything except maybe metal, classical and rap.
They're not bass light, but some may be disappointed in the bass for some reason. I listened to some bass heavy electronic music yesterday and they're not bad at all for that type of music. I was expecting them to be much worse. The only problem with them is that they do have somewhat rolled off highs. They also need a lot of burn-in and sound best with a small amp.
K77 and K99 should also be good, but they probably have even less bass, but just as good mids.
Instead of those i'd look for an open boxed k240 Studio. I got mine for only $70. It's one of my favorite headphones. Anyone who liked the SRH-840, would probably like the k240.
It seemed to be better for more genres then my DJ100, but the vocals/mids are not as forward or clear. Slightly more distant, but not by much. The advantage of the k240 is that it has a better soundstage, but worse imaging. It also has more bass. It's also a bit easier to drive then the DJ100.
Maxell DHP-II sounds good as well. It's only $30, but is very fragile. The sound signature is very similar to the DJ100. DJ100 has better build quality and is even made out of metal!