The perception of sound quality is subjective, for my part I like the rendering ... The reason I value 3 star is more related to the functional / ergonomics. - I had several MM50, this time I chose the MM70. I already had asymmetric cord length headphones, I found it pretty good. In the case of MM70, the difference seems excessive length (more than three times the length of the left .....) The cord is quite rigid, so, it keeps a spiral shape and because of its length without dates continues to face .... Irritating .... - The cable reel: Interesting idea, but for my part, did not seem practical to me ... but then not at all ....