Like some had said, it's about finding the sound signature that appeals to you, and looking for the headphones that best encapsulates what you want. Easier said than done though, unless you happen to have access to a headgear shop that allows you to try out the various headphones. In my neck of the woods, there's a headphone shop that incorporates a cafe, I went there a couple of times to have coffee, and try out a couple of headphones while I was there.....they have entry level gear up to top end electrostatic cans.
I like brighter sounding cans (hence I have no problem with the Beyerdynamic DT-990 Premium and DT770 Pro which I happen to have), heck, I can even handle the sparkling highs on my HD800! There's a crystal clear clarity in the sound that I find somewhat lacking in other headphones. Don't get me wrong, if the treble is too sharp and sound very grainy, I'd not like it as well. Know the kind of sound you like, if you do, half the battle is won already.