Now i have had these bluetooth headphones 2 months and i have to say they are very good. Only thing why i don't give 5 stars is that you have to take a little bit more time to put them in your ears. But when you get them properly set in you ears they fit good and the sound is excellent. Battery will last many hours and i like that i get battery icon in your iphone so you see how much you have battery left. I have used these headphones in running, boxing and weight lifting and they stay very well in my head. I said that these headphones are best in sport what i ever tried. And i had tried lot of different pairs of bluetooth sports headphones.