Summary: I got these to use while running. Other reviews have stated that they stay securely attached to the ear while working out, but I didn't have the same experience while jogging; they loosen and start bouncing around after a mile or so, and as you sweat, then start requiring adjustment every half mile or so. Interestingly it's more of a problem on my left ear than on the right. I've tried all three of the included sizes of earpieces.
Pros: Allows Some Ambient Noise, Comfortable, Good Value, Great Sound, Lightweight, Sweat resistant
Summary: They were bigger than I expected, but so light weight that it didn't matter. Perfect for my morning run, I forgot they were there. They are probably not great for someone who wants sound great sound quality, but I like to hear the road when I run so I think they are great.
Summary: I use the head phones at the gym, got really tired of other head phones shorting out on me due to sweating. The head phones could clip on to the ears a little more snugly, but other than that its a great product for a great price.
Pros: Comfortable, Compact, Good Bass, Good Value, Great Sound, Lightweight
Summary: I was disappointed to find that these headphones start flying off my (normal-sized) ears two miles into a jog. As soon as they become slightly sweaty, the mild bouncing throws them right off, no matter if I run the cord down the back or the front. It doesn't help that the wire includes a heavy and redundant volume control knob. The one good thing I can say about these headphones is that they haven't shorted out yet after about eight miles of running.
Pros: Durable, Maybe
Cons: Falls Off/Out Of Ear, Poor Value, Uncomfortable
Summary: I own two sets of these headphones; one orange and one black in color. I use my Black ILUV i303 In-Ear Clip Sport Headphones with my Classic iPod when commutting to and from work. The sound reproduction is great! No complaints about the bass or high ranges. I do get a bit of ambiant noise, which I prefer! I don't want to shut out all noise as I'm using the Washington DC Metro Rail and Shuttle Buses daily.
Pros: Comfortable, Compact, Durable, Good Bass, Good Value, Great Sound, Lightweight, Stylish