Poor build quality
The two stars is basically for the sound quality. I have always found sennheiser earphones to have good sound quality.
I used these with my iphone for approx 2 months before they broke. Its the connection at the wire and the fack that goes oh so very easily and I wasnt particularly rough with them. A few little tugs every now and then and eventualy you wil loose all sound.
I'd only buy these if you can guarentee that you are very careful with there handling otherwise I recommend a more durable set.