OK, I have to confess that I don't tend to throw much into the Amazon pot of reviewing with regard to (many!) past Amazon purchases but as someone who reads reviews on EVERYTHING before parting with their cash I thought it right I should contribute !! As the review heading says, this review is for the MX685 phones which I took delivery of about a week ago and bought for gym/outdoor running use. These are my 4th pair of Sennheisers over many years and I absolutely love them, though it has to be said that some meet my needs better than others. The clip in ear method has changed slightly over the years as my first couple of pairs were held in my ear by a small disk above the actual earphone and this system (on the biggest disk) worked perfectly for me. Much outdoor running, cycling, gym work with no problems at all. I recently purchased some CX 680's (bright yellow) which I keep at work and they are great. These however are even better. Sound is just as deep but less tinnier than the CX 680's...... and at the time of writing this I am listening on the iPhone to early Led Zep and Iron Maiden and it sounds awesome. Live albums (which I prefer to listen to in the gym most of the time for some reason) sound fantastic through these. Yes, it's all about the perfect fit and I can't stress how important this is. Select the right size collar for the earphone and adjust the ear grip to the right size and you'll be laughing. My one criticism is that older pairs of Sennheisers used to have one earbud on a longer wire than the other which allowed it to go round the back of the neck rather than having the wires dangling under the chin when running like these do. That said, I still sit the right hand wire behind the neck and clip it to the collar of my running shirt with the handy peg clip which comes with the earphones. A small thing but not worthy of knocking a star off !!