Cons: Hard-to-drive, bad strain relief @ plug
I'm not too experienced of an audiophile, but out of the IEMs that I've tried, the UE 500s are the most balanced that I have heard to date. Compared to the Klipsch Image S4 (to which they seem to be compared most often, due to availability), the Ultimate Ears are more detailed and balanced. Whereas the S4s seem to have more of a v-shaped (Bass/treble-heavy) sound, the UEs have a more balanced (some might say bass-light) sound. However, though the bass is not as heavy on the UEs, it is very nicely textured and is less boomy than that of the Klipsches. In addition, the UEs provide a very good seal and isolation, and can be comfortable worn over-the-ear or straight down. The only caveats that I have are that A) they can be slightly harder to drive than mainstream IEMs, requiring 50% - 70% volume on my iPod nano 2G, and B) the strain relief at the right-angle plug is nonexistant, leading to some concerns regarding durability at that strain point. All in all, though, the UEs are excellent IEMs, and are also relatively easy to acquire, as Best Buy carries them in their brick-and-mortar stores.
