Pros: Comfortable, Block outside sound
For months I did not have a pair of earbuds, headphones, in-ears, ANYTHING to use to listen to my music. I did some looking around in Best Buy and online and decided I wanted the Klipsch Image One II headphones. When I went to the store, they were out of stock and I saw these farther down the aisle. They're almost a third of the price, and made by the same company; I have only heard good things about their product, so I figured I'd give these a try. I was a little tentative, though, because the last in-ears I bought did not stay in no matter what size tip I tried....
Anyway, I've been using the S3M exclusively for weeks now and I'm happy with my purchase. They are comfortable and isolate my music; they effectively block outside noise in the house like the TV, cooking, a vacuum. Klipsch's design of angled tips make them easier to insert into my ear.
I'm no audiophile, but these in-ears give me the isolation I want, and provide nice sound for my listening pleasure. So I guess if you're a music fan but a new person to the headphone market and don't understand all the specifications and measurements (like me), or a casual listener, give these a try.