These little guys sound amazing for the money - does require about 24hrs of burn-in before things loosen up and sound right.  Even, full bass due to the added port over the E3's.  This was my second pair after the cable separated from bud after about 1-year's regular usage.  The second pair died the same way.     Unfortunately Shure botched the design in the new versions which don't sound nearly as good, and are larger so they don't fit smaller ears anymore.  It's too bad because these were a real winner.  All that was needed was to improve the...