There is certainly room for improvement.
I want a W4 with a fuller sound....more bottom end. I want a W3 with a bit more midrange and clean up the midbass.
These products don't exist.
It's called the SM64.
Have been listening to the FAD Heaven S. Same price range as the W4. More bottom end, more sparkle (not sibilant) on the high end. Beautiful! Still keeping the W4's, as I want to try them with the 100ohm resistor (totally based on Head-Fi'er suggestions). Would never talk anyone out of the Westones, they're great little iem's.