I'm going to make this short and sweet. First off.. I very RARELY give out perfect scores.. but if something deserves it, I absolutely WILL.. I've been using the Jaybird headphones for almost 2 years now starting with the F5 Freedom.. I'll just run down a shortlist of what I think about these new (for me) X3's * Jaybirds are the FIRST headphones I ever got that doesn't break from my heavy sweating. I really really sweat alot!! I am 6'4'' with alot of energy and I run for about 3-4 miles 4 times a week. * These headphones are in my opinion 100% customizable. The most comfy way for me to wear them are actually none of the styles listed by Jaybird.. but I still give them the kodos because the product gives me the option to figure out whatever works best for me. *The sound quality on the F5 Freedoms was good... but these x3's are ABSOLUTELY PHENOMENAL!! and I am an Audio Engineer and Music Producer, so I know exactly what I am listening for and listening to. Sound quality is Phenomenal.. Plus the app gives you FULL 100% CUSTOMIZATION!! Which is amazing in itself! especially when you understand audio frequencies enough to fine tune the output to literally anything you like. *These things have amazing durability. **Buy now some of you may be thinking that I was paid to write this.. but absolutely not! The main reason why I am really so in love with these headphones and the Jaybird brand.. is because the PRICE that you pay for this level of quality!!!!!! THAT'S really why I am praising these headphones and even Jaybird as a brand so much right now!! Cause I appreciate when a company and it's employees are slaving themselves for countless hours to deliver us (the consumer) the absolute best product possible.. for a price that many of us can actually afford!! Thank you Jaybird.. I can really appreciate these, and your brand! 5 out of 5 stars from me