Sound mediocre, control via headset keys poorly implemented.

Models:

AKG K845
Bose AE2W
Beats Wireless 2013/14 version
SMS Audio Bluetooth

When AKG I was a little disappointed.
The sound is very balanced and very clean. In alternative, jazz and even rap he sounded with the Bose clearest of all, yet boring and powerless. The bass is stronger than the Bose, but somehow I of certain Bums was missing.
The volume was a little louder than the Bose but much quieter than in the SMS Audio or the beats.

The AKG can score by clear sound, but the differences from the Beats or Bose are minimal.
Only the SMS sounds vague and Klangbreiig in some songs by Coldplay.

The thing that bothered me the most was the lack of support for the wireless operator. I could neither present songs by pressing a key and put back nor the battery level is displayed on my smartphone. The volume is not synced, saying he was the Smarptphone at full volume and the headphone halfway. This can competitors better.

The AKG is very very loose at the head, thus its purpose of a closed headphone can not be satisfied.
Only the long gestation period by the well-designed ear pads could convince me yet.

Even though I'm not a fan of fashion products micht has the Beats Wireless 2013/14 when sound and function far more confident and different on several musical genres.