Hi guys.I've bought the A&K AK70 and also would like to buy new earphones. I'm choosing between these three: 1. Klipsch x20i;2. Etymotic er4;3. Jays q-JAYS; All of them are reference earphones, the design and form-factor for me are pretty the same, also all of them has balanced armature driver (one or two). I guess, the build quality in all these earphones are also great. So what would you recomend?