I loved everything about the older S4 model except for one very fundamental problem - they have a design flaw whereby, no matter how well you look after them, the internal wiring wears through at the point where the cable meets the jack, so after a few months one of the earphones cuts out and stops working.
This happened to no less than three pairs in a row so, obviously, I stopped buying them after that. Then, I saw this newer model with thicker cabling which, I hoped, meant that Klipsch had addressed the problem and I decided to take a punt.
What a shame then when I found that, after just four months of use, these very expensive headphones stopped working due to exactly the same design defect that the previous model had had.
Also, don't be reassured by the "2 year guarantee" either - it's a bit of a scam as, in the UK at least, Klipsch will not deal with you directly. This means that you have to go through your dealer. If you're lucky then your dealer (be it Amazon or whoever) may honour the guarantee but that is at their discretion, and thus very far from "guarantee'd".
Please don't buy these - the fact that Klipsch is selling these at a premium price but with exactly the same short lifespan is really not on; and when they break (and they will break, believe me) you will regret your purchase.