Compared to these, the Sennheiser MX-550 had a sound a little better defined, especially in the treble, it's not the earphones for bass lovers ... but outside of her, I kept my regret a preference for Sony, which, while cheaper, had a volume control much more precise (that awful slide button on the MX-550 becomes less and less accurate at over time), a cable a little longer (if I remember correctly) and especially ... thicker!
Yes, because what made me part with the MX-550 is their fragility: the cable is ridiculously late. Admittedly, I have still not misused for 2 years, but despite the care taken in every time I ranks, they ended up being victims of false contacts, such as an ordinary pair of headphones two to three times less dear ... shame.
For € 20, I have not bothered to return them as collateral, it would have been costly in postage, especially without the guarantee that the Sennheiser would trade me for what they could consider wear or mishandling on my part. In addition, Sony was always my nickel when I lost.
Maybe I made a mistake: I did not perhaps used enough of their storage box, which might have helped to prolong their life. But then their storage box is really ... need: clear plastic as fragile as that of an animal enclosure at CD, I doubt she would have survived if only a dozen successive storage.
I would do this choice? Hmm ... Certainly, the sound was slightly better than my Sony (but really a tad), but that's all. For everything else, the price difference was not justified in my eyes. My advice? If you can find cheaper with the same features at Sony, it would certainly be a better choice. But it may have changed since ...
Anyway, now I use Shure E2c, and it's a different world. Of course, they are 3-4 times more expensive, but the sound quality and production is infinitely superior, not least at the level of the length and thickness of the cable, or quality of their box ultra-rigid storage.