You never know how quiet it really is until you put on the earphones and turn it on. Its like a "cone of silence".
How does it rate? Well, it does work. I've put it on at home with a noisy aquarium pump behind me and it blocks out most of the noise. On a train to work, it cuts off most of the air-condition and low frequency noise. The feeling when turning it on is like having a cone of silence lowered over your head. Its amazing. We just don't realise how much noise is around us.
Comfortable: Its quite comfortable. You need to push it into your ear and it sits there comfortably. Just make sure that it seals your ears properly.
Frequency response: Its so so. One of the reasons that I'm not giving it 5 stars. Since I listen mainly to speech and audio books, I'm happy with the performance but for those who are into hifi music, I don't think that its that good.
Conclusion: For the price and if you listen mainly to audio books, its good. If you are into hifi music, it may not suite you.