Wehn I bought my first iPod (3rd Gen B&W) the headphones provided were terrible. I then went for Apples own In-Ear headphones and I thought they were the best thing since sliced bread. I did eventually tire of these and decided on a change and got a set of Skullcandy Skullcrushers, these once again upped the quality and I was very pleased.

I decided to go back to In-Ear and read several reviews of the CX-500's and personally they have once again raised the standards of headphones for me, the clarity of the treble whilst dealing with punchy bass is spectacular. I am used to dealing with great sounding audio (seeing as I have a £2000 Rockford Fosgate Car Audio System) and these headphones make my private listening very enjoyable.

I do recommend these without a doubt.

I just got them from play directly. I am a fan of sennhiser. These headphones are top-end in all aspects. They are well balanced, highly responsive across bass mid and treble. Tight controlled powerful bass. All frequency's are very well represented with no distortion. They have a good selection of accessories so that you may get the best sound and comfort from them. Regardless of price theses are outstanding.

A lovely full sound, well made. Block out background noise even better than my old cx300 i don't know how.

Once you get them, you will forget about the money. Don't buy fakes, buy from play.com the price is very good.

These phones are comfortable and they fit securely - as well as having quality build and components.
The sound is meaty in the bass but not overpowering, with a clear and sweet treble and mid range.
I also have the excellent CX300 phones but I have not listened to them since I bought the 550s 3 weeks ago. All I would advise if you are making the changeover is to give them time to be appreciated - it's not a night and day difference - but over time you will appreciate the quality bass and improved levels of detail retrieval. Highly recommended.