I received my first set of Slim+ for Christmas 2017, I have had four pairs of Slim+ since that time. The sound quality was great and the ear piece was comfortable in my ear and they stayed in place while running. The problem I have had is they would not charge after about the 4th day. Customer Service has been great to deal with, but getting the same defective product over and over is a bit trying. After the fourth pair, customer service upgraded me to N10 earbuds. Sound quality was good, but the were not as comfortable in the ear as the Slim+. On about the third day, the connection between the earbud and the cable broke. I contacted customer service again, this time I am going for my 5th set of Slim+ earbuds. I am hoping that I get "lucky" this time and get a set that works. After this, if they don't work, I'm going for a refund, and saying good bye to Anker.