No wear and tear on the USB port. I feel like a ninja in these so silent and grippy. Otherwise, theyre fine. I put my phone volume on high and then the earphone itself, and I was also satisfied with the loudness. Maybe an extra large would have given me that over-sized look that I wanted. So, I gave them a try and ordered a 10 and 11 (usually wear a 10. 5 and I have a fairly slender foot. However, the material used is smooth and hard and can slip into pockets a lot better than silicone covers. Whatever the ad says, the bench does *not* go down into a decline position. Therefore, I need waterproof, sturdy and durable bag to hold the things I need in my travels.