Design and form factor
I searched the world over for a $100 (or less) pair of earbuds with good sound to use with my iPhone. I've probably wasted $300 - $400 in the past three years buying products from Apple, Shure, AltecLansing and others. I never found a product that sounded nearly as good or wore as comfortably as the S4is. There was always a trade-off. I have a pair of Ultimate Ear 5s that I paid over $250 for that aren't getting used since I bought these Klipsch buds. The sound of the S4i is absolutely beautiful! The highs are very crisp and the bass is simply astounding. Deep, rich and never muddy. I would have never believed these were single driver earbuds. To my knowledge, there is nothing on the market that sounds so good for twice the price.