Pros: Non silibant, not fatiguing, small form factor, comfortable,
Bass response doesn't bleed to the vocals or any other frequencies whatsoever, lightweight cable with no microphonics and a narrow plug to connect to portable devices. The Westone has a powerful, detailed and clear sound that does not under or overemphasize anything. A polite sound as another writer described with a mid-bass bump and upper treble elevation without been disturbing. A young-adult/athletic grown-up man sound if I have to describe it.
Some people called holographic sound but I would say it's more like a de-phase between armature drivers.
Westone star tips are excellent, I use them for almost all my IEMs,