Five stars. Easily the best wireless headphones I've used, maybe the best noise cancellation, and astonishingly, I'd say well worth the money.
I'm used to using on-ear noise cancelling headphones, so the biggest difference for me was the enclosed over-ear style. This dramatically increases the noise cancellation, but also had led to a little bit of air pressure on my ears after prolonged use (2-3 hours), which is only mild discomfort that disappears within minutes of stopping use. The noise cancellation is reliable in a lot of different environments; unlike some on-ear models there's no flutter when using outside in windy conditions. Seems to be very little, if any, sound leakage, even at higher volumes in quiet environments (again, better than on-ear alternatives).
Sound quality is very good (definitely better than the typical 'Beats' sound), with a variety of different music and video/voice/phone. And it can get very loud! That said, it's good enough to highlight quality issues with streaming sources; I've switched Spotify and Google Play Music to 320kbps to make up for this. Works ok as a phone headset, although the noise cancellation is so good that it's hard to work out the right level to speak at (without unexpectedly shouting!).
They're comfortable to wear, and the matte black looks great. Doesn't attract fingerprints, and isn't as obviously branded as some other Beats models. The lack of red on the headphones is particularly notable (although one of the included cables was bright red). Materials seem solid enough, albeit a little 'plasticky'. A 'stealth' option, as far as large over-ear headphones go. Packaging is quite large and suitably over-the-top, but comes with a good travel case (although I haven't needed to use this yet).
The Bluetooth stack seems quite reliable (especially compared to older pairs of Nokia wireless headphones I had). Having the battery indicator on my iPhone is a nice touch. I've paired with a few different devices - phones (iOS and Android) and Macs (laptop and desktop) - without any trouble at all. Pairing is fast and it reliably reconnects to the last device I used. The only annoying part is that the Mac media controls aren't activated by the Beats button on the headphones (this is an Apple issue, and not unique to Beats).
Speaking of which, the single Beats button is overloaded a bit. Pause/play is an easy single tap. Previous track (or usually 'start of current track') is a triple tap, which I find hard to time accurately every time. To go back to the start of the previous track can take six taps on the button, which is crazy! Next track is a more realistic two taps, but even that can be hard to get right. Adding two buttons (for previous and next track) would be a nice touch, it's just overloading a single button to do so much. On the other hand, volume control works well, and links to the volume on your device where possible (so it's in sync with apps and the device volume keys).
Battery life has been great so far. I'm curious to see how I go on a couple of long flights (it certainly won't hold out on London to Sydney, and I'm not confident about London to San Francisco). The design of the headphones makes it hard to accidentally turn them on in a bag or their case, which is good - I've had a couple of pairs that suffered from this in the past (Beats and Nokia). Standard micro USB charging, worked with all of my different travel chargers, and was quite quick from wall outlets, portable battery or laptop computer. Only drawback is that you can't charge and use the headphones at the same time, but the rapid charging time makes this a relatively minor problem.
They tick a lot of boxes across the board, without a doubt. I haven't used them wired, and probably won't. There are competitors with 'smarter' headphones that turn on/off when you fold them, pause/play when you remove them from your head, and have enough buttons to support previous/next track easily. But they all have their own drawbacks (mainly around Bluetooth and audio quality), and the Beats are brilliant at what they're designed for - active/passive noise cancellation whilst listening to great sounding music wirelessly over Bluetooth. They're not perfect, but they're the best option I've found, and although at a high price point, I think they're good value for money.
So that said, here's what I'd like to see in the 2015 (v3.0) edition:
* Automatic power on/off when folding the headphones (simple switch sensors)
* Automatic pause when removing headphones from your ears/head (proximity/pressure sensor)
* Better support for audio/media controls on MacOS (Apple's problem now)
* A better way to access previous/next tracks (is it too much to ask for another two hidden buttons on the earpiece?)
* Less bright LEDs when charging (in a dark room they can be very bright; ambient light sensor?)
* Ability to use the headphones while they are charging (good for ultra long haul flights, like London to Australia)
* Black cable for microphone/remote control connection (this is red, even in the black edition - the 'plain' cable is black though)
* Better protection before shipping - one ear cup was slightly crushed (other reviewers also reported this)