Pros: Sounds half decent, bass not too woolly and treble not too harsh
Cons: Cable will fail you, even if you treat it like it an angel. Cost doesn't reflect quality.
I've had a very bad experience with these headphones and as such will personally not be buying Klipsch again. I'm now on my third pair of the the S4A (II)'s - the version specifically for Android smartphones. All three developed the same issue, losing sound in one channel. There appears to be a significant design flaw in the cable as in all three cases I was wither walking along with the phone in pocket or doing another everyday activity like mowing the lawn and the channel just cut out to such a degree I was never able to determine the location of the break by manipulating the cable, plug or joints.
The local Klipsch local distributor replaced the first and second pair (begrudgingly), but now says Klipsch have told him that they won't replace any more devices purchased outside of New Zealand - (these were a gift from my father in law from Amazon UK). That's understandable I guess though, so I will try going back directly to Amazon and claim they aren't fit for purpose, but they are outside the 1 year warranty now of course. I have to say that I am really disappointed that the product appears to have not been tested to cope with normal use - it's not as if I was jogging or doing cartwheels or yanking the plug out of my phone sideways etc - just walking or mowing! It is especially annoying, as after the first replacement I have been ridiculously careful with the cables knowing how fragile they are, yet they still failed after only 3-6 months each!
I am happy enough with the sound quality, it's certainly a significant jump up from bundled headphones, but they weren't mind-blowing in any particular regard. OK bass and mids, treble a bit muted but I prefer that to shrillness. Isolation was very good, with the oval tips fitting my ears well, and they're comfortable over moderate periods. One unwelcome thing I noticed however was that when making calls, there is no feedback from the mic to your ears, meaning with the isolation you can't tell how loud the environment around you is, nor hear your own voice well and therefore can talk too loud - it's a bit disconcerting at first. Things are actually better if you pull the tips out to reduce the isolation. FYI the mic appears to work OK in quiet environments, not very well in noisy places, and is located not hanging in mid-air underneath your right ear like Apple, but rubbing on your centre of your shirt, Also, the lazy blanking of the Apple remote buttons to leave one available for Android means the controls are unnecessarily oversized and heavy.
OK, enough ranting. Get these only if you see them cheap, say US$30, otherwise buyer very beware!