I bought my Shure's about two and a half years ago, and at that time, I paid 60 quid, which was a bargain then.
Initially, I was shocked by the size of them, and they did feel a bit big in my ears to begin with, but even during my first session they started to feel comfortable. Now, I'm using the middle-sized plugs and even THEY feel fine. Basically, these are the most comfortable earbuds/plugs I've ever worn. Heck, even my super-comfy Sennheiser home-phones aren't as good as my Shures for extended wear.
Though I do enjoy good sound quality, I'm no audiophile. All I know is that these things let me hear things in songs by my favourite artists that I had never noticed before. They're very clear and direct due to the in-ear nature of them, but the sound is also soft enough that even though I am aware of artefacts in 128 Kbps mp3 files (which I no longer use), it doesn't destroy the experience.
The only thing that bothers me with these plugs is that while the over-ear loop is very comfortable, all the coiling and uncoiling has managed to break open the wire so I've had to tape up the wire that goes over my ear, making them less wonderful to wear. I would have liked it if some kind of an extra came with them to keep them in the looped position but didn't take up a lot of space around the ears so they'd still be comfortable to wear.
Other than that, though, and ESPECIALLY for this price. I'm stunned to see them costing this little, to be honest. Safe buy.