I use earphones like this at work. They get destroyed after a few months, so naturally I always buy a cheap pair.
I bought these because they looked pretty comfortable and the reviews were good. They are the worst earphones I've ever had.
As I type, I've just replaced the one in my ear with a £3 pair of JVC earphones I found at the bottom of my drawer - ahh, much better.
DO NOT BUY. Even compared to this £3 pair, the sound is absolutely awful, they feel cheap, they are uncomfortable, the leakage of sound is horrendous, and there is no slider to gather the earphones together when not in use.