I really like these. The build seems great for the price. My previous ear buds were Sennheiser CX300-B which lasted me a long time, but these sound much better, and are build a lot better. I don't have experience with expensive IEMs, but then again these aren't expensive so what do you compare them to?
I only wish they came with more replacement foam tips. Those silicon ones make them sound horrible.
Also, wish the cable had some tactile...