I had a pair of UE Superfi 5 Pro.. ended up selling them on ebay about 6 months after I bought them... I felt they lacked clarity and definition, but I suppose thats what you get from ear buds, relying on your canals to enhance bass...
Im hunting for a pair for the gym, not at the same budget though.. I feel the only way to get tru hifi is with closed headphones, but they trying to find some that are discrete enough for out of the house wear is hard work..!!
Id put up with the default iphone headphones, but they just keep falling out of my ears!!!!... looking for neckband or even ear hooks.. but fcant seem to decide on any.. Trouble is buying headphones, you really need to try them before buying them, but with limited sotck in most street hifi shops, its difficult...