I realize I am a little late to this party, but here is my input.
I just picked up a set of the AE2's, and they are not yet broken in (never liked the term "burn in").
As a bit of background I have tried/owned various Sennheisers, a pair of Grado sr60's, Koss ur55's, and some others. So my experience is not with the extremely high priced or "boutique" brands, but run of the mill models by well known companies. Although I do not make my living at it, I have also been a musician since my mid teens (I'm 59 now. That's right. I'm an old fart!) so music is not something I have just recently discovered. Most of my listening is to music of my younger years. The Beatles, Stones, Moody Blues, Cream, Hendrix on one end, and lighter fair such as Simon & Garfunkel, James Taylor or John Denver on the other end, and artists like Harry Nilsson somewhere in the middle. Heck, you might even catch me listening to Nat King Cole on some days. Absolutely no rap, hip-hop or country. OK, MAYBE a Kathy Mattea song or two, but I promise that is as country as it gets with me.
I agree with another poster in this thread that the discussion should perhaps be more about the sound and comfort (making longer listening sessions more pleasant), and less about brand name or price, to truly evaluate these phones. That being said, here goes.
These are without doubt the most comfortable phones I have tried. Some of my other headphones have been either too tight or loose (the Senns), and some downright uncomfortable (the Grados). The Koss were unique in the flexibility of the headband, and thus were easier to adjust for comfort. These however, are darned easy to wear. No, I won't "forget that I am wearing them" as some claim about some headphones, but really darned comfortable. They are not the sturdiest I have seen or worn, but they certainly feel like they will last a good long time.
By the way, I am listening to music on a Sony S545. No additional amp (and no intent to buy one). Some of the music is recorded in lossless WAV format, some in MP3 VBR average of about 296 to 320.
Now, on to the sound.
I'm pretty well pleased with these AE2's. For example, the Moody Blues can sound a bit dark on some phones, in particular the Senns with their signature sound being a bit that way to begin with. By contrast, the AE2's bring out more in the music. The Koss phones do this as well, but not quite the same. Nice presentation overall. With The Beatles, these phones are nice and balanced. Perhaps Paul's bass could be better represented, but that old Hofner of his had a very mellow sound to it to begin with. The bass representation may change with time and use. We'll just have to see. But it isn't bad at all.
On acoustic music these phones really do a terrific job. S & G, Denver and Taylor all sound great, and vocals on all the different music sound very good.
So, if the bass gets better with time and use, I'm going to be very happy with these. You might notice that I made comparisons with my Senns and Koss, but not the Grado. The reason is I have never been able to bring myself to say anything nice about those. They are uncomfortable and shrill and I regret buying them. Yes, I know they are the holy grail for some, but not for me. I would not, however, spit on anyone wearing them, nor would I mock that person or their family as one poster so inelegantly put it. I've just always been one to believe my ears more than put stock in any magazine review that tries to tell me what I should or should not like.
So, there's my opinion, for what it is worth.
Thanks for reading, and be sure to tip your bartenders and servers on the way out.