It's worth noting that there are five variables involved in assessing headphones/earbuds.
() the kind of music/sound being reproduced
() the connection between the source and the listener
() the capacity of the listener to discern differences in sound
() comfort and convenience
() personal taste
The bottom line is that a tin can on a string is probably sufficient to listen to an old Jack Benny program (which I admit is a guilty pleasure of mine) or much of what passes for popular music. A Mozart symphony, on the other hand, requires either a set of headphones/earbuds tuned for such music or a pair of highly flexible (and usually expensive) phones. The bass heavy character of much current popular music has led to development of a number of models that provide an interesting experience but sacrifice subtlety in favor of heart stopping thumping. To each his/her own.
Wireless headphones will not sound as good as wired headphones. Period. If the difference is not apparent to you see item #3 above. That's not a snide remark. If you hear the difference you hear the difference. If not, it's because your ears/brain aren't triggered by more subtle differences in sound. Content yourself with enjoying the freedom of wireless headphones. It's not an insignificant advantage. If you're like me, you put up with cursing the damn wires because every bluetooth headphone I've ever tried sounds like a 1965 Princess phone.
If portability is a primary requirement, be prepared to sacrifice some in terms of sound. And if you listen to music in noisy environments the fact that noise cancelling phones tend to "flatten" the sound may be unimportant since you couldn't hear the subtleties anyway.
For earbuds, my priorities are that they sound VERY good and stay in my ears. That means they're going to be uncomfortable after awhile and so the sound better be worth it.
For listening to music on my iPad, portability is a priority so I use the Sennheiser model in the above post or a pair of Shure 215 earbuds stuck far into my ear canal. If I'm flying I use the Shure's that isolate me so completely that we'd crash before I noticed or the Bose Comfort 3 noise cancelling headphones. (They degrade the sound compared to comparably priced phones w/o noise cancelling but they do an effective job of reducing the roar of the engines.)
In short, it is always a compromise. My six year old's favorite earphones have pandas on the cups. For her, looks trump sound. Hopefully, she'll retain enough of her hearing by the time she's 25 to make a more sophisticated choice.