I have owned several top branded in-ear earphones - Sennheiser IE7, Shure E3c + SE530, Klipsch Image S4 etc. - but have found that when going to the gym the earphones tend to repeatedly slip out of my ears.
These are the first 'sport' earphones I have owned and I have to say I am disappointed with the sound they produce. The earphones themselves stay in my ears and the design of the ear-pieces is sturdy yet flexible to suit most ear shapes, if a little bulky. The sound however is flat, muddy and lacking any sort of soundstage. They deliver decent bass but there is no clarity at all to mid or high tones.
If you just want earphones to pump any old sounds into your ears whilst working out then these are for you but if you care in any way about the quality of the music you are listnening to then I can only advise you to avoid these.
I will be trying the Atomic Floyd SPORT AirJax Stereo Headset with Remote next....
Okay so instead of spending lots of cash on the Atomic Floyds I thought I'd try another pair of more modestly priced earphones first. After some research I opted for the Sennheiser OCX 685i Sports In-Ear canal Headphones
with remote and the difference is startling. These produce a rich, clear, natural sound with a distinct soundstage and I must say I am very surprised that £50 can buy you such quality. They also stay in my ears during my gym workout and I would highly recommend them.