I've always had trouble buying bud earphones because they always keep popping out of my ears, but with these, you get three sizes included with your earphones and the smallest ones are perfect for me. I also fund earphones don't last very long, but I've had these a while now and they're still going strong.
I have tried several different small in-ear headphones (Sony, sennheiser, JVC XX etc.) and these are by far most comfortable, and reliable, with a fair sound quality for the money. Cannot fault them for under £10