I'm a bit of an earbud geek, though I wouldn't pay over £150 because I loose them.
I have owned Bose, Shure, Sennheiser Sony, Apple (the expensive ones), V-Moda and etymotic
Best bang for buck is the Sennheiser CX300, which you can get on ebay for £10; the Sonys (71 somethingorothers) are great general everything 'buds but I have settled on the Etymotic Hf2- Not great bass, but incredibly precise.
I had warranty problems with the V-Modas and my last etymotics which they replaced (without asking for the originals back) for a set with a different plug design. I franken-hacked the old ones onto an iPhone earbud jack and microphone FTW
Avoid all Apple ones like the plague. They only fit a 5th percentile of humans.