The headphones are well balanced and comfortable to wear. Even while jogging it does not interfere.
You sweat a little on the cushions but this is also with any other headphones so and therefore not to be regarded negatively.
The sound is in my opinion Neat but for me the sport somewhat secondary.
The control buttons are well placed and usually are also found immediately the right button.
The smartphone does not react with a delay of about 1 second on the inputs. However, this is through the radio link conditions and therefore for me no criticism.
Each of a small, lightweight Bluetooth headset searches should pick up the Sennheiser 400X.
The newer model has 450X think I times a little bessernen sound because it has a built-in subwoofer and therefore the bass are better.
For me it was the best choice and I can only know about each other.
The 450 I did not buy because it then do it again a bit is more expensive and I do not put much emphasis on music quality to me. After all, I've been using it for sports and not primarily for listening to music.
