Conclusion: Iwas disappointed after my first day. the rubber tips are so thin and flexible it's hard to get them into your ears. I have an apple classic Ipod and I messed around for a half hour with the bass, loudness, treble, eq functions and I could not get as good of sound as I could with the factory ones that came with the nano pod. I bass sounded like it was maxed out way sooner than the factory ones.
Summary: There is way too much cable noise caused by movement of the cables. I would find these devices impossible to use while running or exercising. They are almost impossible to use while walking. I would only recommend them with reservations.
Summary: I bought these for use with my mp3 player. They do have rich bass and they are reasonably comfortable. Sadly, I feel the cons may outweigh the pros. I wear and remove them frequently which is a hassle because for them to work properly they must be placed in the ear like an earplug. (Other hand around the head tugging back and slightly upward on the ear while inserting) It makes for a more time-consuming install.
Summary: This did not live up to my expectations. It would probably be an excellent choice for airplane travel or other sedentary activity, but it is terrible for anything active, such as working out or walking. The ear buds completely block your ear canal, similar to a set of ear plugs, so if you find those uncomfortable, you will find these to be no different. With the ear canal blocked, all your internal noises are much louder - breathing, pulse, etc.
Summary: I liked the ear fit - three sizes are provided and I liked the sound, really sharp and powerful. However ... The asymmetrical cable is awkward and is a bother. From the yoke (where the bud cables separate) the left ear bud cable is 7-1/2" in length. The right side bud cable is 21" long. That's quite a difference. The CX-300 is designed to be worn behind your head. I wish the cable measurements had been printed on the package!!
Summary: These earbuds sound great if you don't mind holding them snug in your ears with your fingers. That's the only way I was able to get decent sound out of them. And that's after using all three avalible bud attachments.I have since returned them at a loss of about 15.00 dollars on shipping to and from. I am going back to my over the ear boise, a little bulky but excellent sound and no cord problems.
Summary: So, the other reviews are fairly accurate. I bought (two pairs of them!) a while back and I thought they were good, Senheisser brand made me feel smart. If only I had come here first (or known about head-fi) I could have made a better decision. At $40 they're not worth it at all. If you're willing to drop double that get the RE0s, they will not disappoint.
Summary: Bought these as a cheap iem to use while my customs are being fixed, they sound pretty good for the price, isolate well enough to be bearable on the train, and weren't too expensive.
My problems with them come from the entire design of both the iem's and the product as a whole.
Plastic death packaging is awful, physically getting the phones out of the package was infuriating, rather than a pleasure, even with scissors, and a stanley knife.