I am an avid runner and I am trying to find the perfect solution for wireless running music. I have killed three pair of Motorola S10-HD, and two pair of Motorola S11-HD. I have tried several other options and nothing seemed to fit or function as well as the S10 HD up until now. The Outdoor Tech Orca, caused a lot of ear pain, the iKross A2DP were just flimsy and didn't stay put. Enter the BackBeat Fit. Better than any wireless solution I've tried to date.The headphones aren't a rigid wrap around device like the S10 and S11. Instead they are a pliable rubber that comfortably wrap around your neck. You never know they are there. Let me reiterate that, they are so comfortable and light that you really don't notice them at all. Since purchasing these I have gone for several 5 mile runs and a 13 mile run. There is zero ear fatigue. They are not held into your ears by the wrap around piece so they don't press in on your ears. There are no "blades" as with the Jaybirds and Orcas to press into your skin. Instead they wrap comfortably around your ears and there is a soft D hoop integrated into the ear bud that just helps keep things in place.Functionality is great. The buttons are easy to find when you are on the move. Once you take a minute to read how they function it becomes very intuitive. The button presses are crisp and responsive. The audio on these is good for me, and the voice headset is clear to those I talk with. I've used them for a couple of conference calls at work and they are very nice. I updated the firmware with the Plantronics Update app from my phone, that was a simple process. Additionally, there is a pretty cool, albeit, limited feature that lets you find your headphones if you've lost them. Assuming they are powered on and synced to your phone you can enable an audible alert to track them down. There is also a method to track them down using a "backtrack" method, but I haven't found that too useful as of yet.Battery life is fantastic. I finished a run that was nearly two hours, and when I checked the battery level on the Plantronics App on my android phone, it indicated I had 81% battery life and over 7 hours of listening time remaining.I perspire quite heavily when I run/exercise. This is what has killed every other wireless running headset I have had. Additionally, I live in the pacific northwest where we get a lot of rain. If they can survive me, I think they could survive anyone. I'll continue to update this review as time goes on. Plantronics offers a 1 year warranty on these. I hope I don't have to use it. I have already purchased a pair for my wife. She has tried them and loves them too. I stared at these on Amazon for far too long. I wish I'd purchased them long ago.Update 10/12/15So we now own two pair of these. I have the blue and my wife the yellow. Couldn't be happier with these still. I just finished a marathon running with these and every training run from July to October. I've ran over 350 miles with these, used them on countless conference calls, listen to music and audio books. I have no complaints. My 4 year old used them as a water toy, for about 15 minutes, in his water table in our backyard and they are still functioning fine. The battery life on these is ridiculously good. Highly recommended.Update 12/15/15Well, I just created a return/warranty request for my blue pair. The Play/Pause button has stopped working, and the volume button seems to be stuck and the volume goes down all the way. These are still, by far, the best headphones I've found for running/exercise and general use. I have really put them through the paces with sweat, rain, in and out of my gym bag, use while doing yard work, etc. I am interested to see how the return/replacement process goes with Plantronics support. So far it has been simple and my return has been authorized. I still highly recommend these for everyone. The yellow pair are still working well.Update 12/16/15I just received my replacement headphones!!!! So that tells me that Plantronics has an efficient and effective return/replacement customer support service. It took one day to receive the replacements. In the midst of the holiday shipping madness, it took one day to process and ship out my replacement request. So they clearly don't wait until they have received the old pair prior to shipping out the new pair. Now I have another reason to love this product. I did have to pay the shipping to send mine back, but at this point I don't care.