Summary: Cheap, cheerful sport 'buds on clips'. They're a huge improvement over the older MDR-J10 which don't come off when pulled, so these rubber clips allow the buds to be pulled off (by accident) which saves the cable from breaking too easily when snagged.
No real improvement on sound quality over the older design which is quite muddy like most buds, but other than that, it's difficult to knock them.
Summary: I too returned this product within a day of receiving them in the mail. I was extremely disappointed because I was looking for new headphones to replace my old Sony headphones, which I loved but accidentally broke. The earpieces are too large and fall out of your ear almost immediately... definitely wouldn't recommend if you're planning on running.
Summary: Like many others, I was looking for something that won't fall off my ears while working out. This product wouldn't stay in if I walked across the room. It is not adjustable (though the product instructions tell you to place them in your ear and adjust), does not fit snuggly over the ears, and the actual ear piece is quite large. I opened the box, tried it on, and immediately returned it. Save the $4.50 return fee and stay away from this product.