I swim Front Crawl almost every morning at home. I am not a playlist or MP3 person so I did not buy it for that purpose. I like to listen to Pandora on my iPhone when I swim. Before I had a speaker next to my pool but I have not been enjoying it much so I thought I give this a try because I did not want to pay for those $100+ ones and this really met my expectation at its price. I’ll keep it and I hope it will last long in pool. I do Front Crawl for about an hour or so. I put my iPhone next to the pool and played pandora and really enjoyed listening to the songs on this headset on Bluetooth mode while I was swimming. Actually it’s a plus that it stays next to my ears so I can use my own earplugs. By the way I noticed when I put my earplugs I hear the songs even better! Yes few times it had hiccups when my head was completely under the water but overall it was not an issue for me specially that in Front Crawl my ears are almost close to the surface all the time. Just to confirm I exhale inside the water, face down, and I had no disconnection during exhale. Anyways, I could hear the music all the time and I enjoyed my swim. It did not work for backstroke. Breaststroke neither. But I don’t do those so I’m fine. Again this review is for Bluetooth connection. MP3 mode should work for all types of swims. It did not fall off my head, it did not bother me either! I did not need swimming cap.I did not expect it to be a high quality headset, because I go for a swim and sweat not meditation! And I am not comparing it to my other headset that I use during the day. I don’t think these kind of headsets would meet anyone expectation for anything other than sport. I just wanted to listen to Pandora while I swim and for that purpose I can hear it well enough and I am happy.I gave **** Stars all the way through for this product. I probably would have given it a 5 starts rating if the answering phone call button would ha been on the right side of this device instead of everything else being packed on the left side. I like the design and it's not that heavy at all. The device is all black and it's very easy to use. The "+" and "-" volume fuctions are on the left hand of the unit. So your in good hands because it comes with a little booklet to help you use your device. I've called many of my friend's to ask them how clearly was my voice coming through and then I've asked them on a scale of 1 to 5 how well is my voice plus the connection? And I've got the answer of 4 on each account. And I most definitely like the mp3 player because it holds and play all my favorite music! I can leave my cell in my bed room and run around throughout the entire apartment and never get disconnected. I haven't tried going swimming with them yet but that's coming up soon. I was outside with them when it and after the snow melted that hit my face and the sides of my head and then melted it did not harm my device in anyway because like the product says it's water proof. Now if I'm to far away from my cell the unit will definitely let me know by saying, "Disconnected!" And whenever I connect my cell to the unit it say, "Connected!" Now this is a product worthy of having.There is big gap between the back of the head & connecting cable/parts of two sides. During walking, jogging it is OK, but unusable in any lying , relaxing or backward leaning postion.Can the cable be bent downwards to make it comforable & usable for relaxing position?Tenia otra marca y no eran tan pesados. Despues de unos minutos son incomodosSo far (2 Months), it has been working great. It feels wonderful when listening to music under the water.I love the idea of its own internal memory. I down-loaded hundreds of songs.Love the sound but the comfort is lacking. The bar B between the “ear” pieces needs to be adjustable as it always feels too big in mg head.It works well if you don’t want to use the Bluetooth functions. For the first few days, it worked well with my PC (which is why I initially bought it). The Bluetooth function would NOT work in the water, but I was able to add a few songs onto it and that worked fine. I would put my phone as close to the pool side as possible and it would still disconnect after going a few inches under the water. After the first week, it had issues keeping connected with my PC and when it was consistent the audio would lag behind the video. There was a major delay in the sound which was not ideal.I bought these to swim in a swimming pool. I use them everyday and they work very well. Some aspects to consider:1. Buttons could be hard to manage and you need to push hard to make them work.2. Songs with bass sounds might have lots of distortion when underwater. You will need to dial down volume to get some quality sound3. Charge lasts about three hours when working MP3 mode4. Due to the shape of the headsets, it could be hard to find the right position and wearing a latex cap plus goggles makes it more difficult to adjust. You can't wear them over the cap, so what has worked best for me is to adjust the headset and then put on the cap.In Bluetooth mode these headsets are very good. Sound is very clear and manages very well call support. For the price and functionality, these are a very good purchase.El volumen es bajísimo. No me sirven ya que mi entrenamiento es contracorriente y no escucho nada.No sirven para natación y probablemente para nada.