I chose this helmet following the advices and reading test in a journal. This is an excellent value for money. The port is nice because the atria surround the ear without relying on it which makes it very tolerable for long periods without fatigue. The plus of the clamp bracket allows to always have it at hand. Listening is very detailed and it forgives nothing to sources of bad quality. It offers a very good front-back spatial sound with instruments that seem placed around itself, which is rather rare for a headset of this price range. With its relatively low impedance for Sennheiser we can use it on an MP3 player without having to push the volume. But attention to the quality of recordings. I used it on an iPod Touch and on You Tube where there are good and bad! However, the CD is really very good. I find the quality of my speakers, but without having to generate a high noise level, which is great for my entourage. Pending the HD800 (in another price range) is really excellent headphones Stereo that I recommend without hesitation.