Conclusion: Good sound, the cord doesn't get tangled, and they stay in ear really well. What's not to like? The only issue I had is that the built-in controls don't work for some older devices, but as long as you check compatibility first you should be fine.
Conclusion: Since purchasing i have found other Sony headphones that give better sound quality and lasted longer. These things pop out of your ear too quickly. Don't run with these. The "tangle free cable" is tangle free, but it sticks to clothing way too easily. Sticks to almost everything actually. It doesn't stop sound like it says, it only isolates it slightly. No in ear headphones can stop sound from coming in from the outside world. Worst headphone I have ever owned.
Conclusion: These headphone definitely block outside noise and are comfortable to wear and have good sound quality. The only thing I do not like is when I'm wearing them while exercising any movement of the cord is amplified in the ear buds. For that reason alone I would not likely spend the money to purchase this item again.
Conclusion: I really fell in love with Klipsch S4's with my black s4i's but those broke after about 1.5-2years of use (rough gym use included) and couldn't really imagine using any other headphones. Came across this website with a nice discounted price for the white s4's and never looked back :). Also bought the Reference s4i from here for my girlfriend, she really loves those as well.