Ear phones that stay put?

[varaonaid]

I've been using "earbud" type headphones for probably 15 years now. My current pair of Sony's I splurged on around 10 years ago and I'm finally hearing some distortion going on. I figure, it's time for an upgrade. I really like the canal or in-ear type phones but I have a specific requirement that they stay in/on without falling out. I'm a dancer and will use these to choreograph/rehearse so they will get quite a workout turning etc. I have been quite set on Sony's EX81's except for a couple of things I've recently read on this forum. The first is the over the ear thing working. I'm only 5'3" and don't have big ears so will the over the ear clip work, help, hinder or otherwise? They don't necessarily have to fit perfectly for the ear clips to "stop inertia" and keep the phones from flying off. My second concern is the quality if the cord which seems to be in question currently (though perhaps less so or unknown for the EX81's than Sony's previous models). At the moment I only have a hard drive player but will likely add a flash based music player in the very near future. This would be worn with an arm band if that makes any difference on the ear phones.

I *gulp* might consider the ER6i's though for my budget, that's a real stretch. My main concern is that they won't stay in when I'm very active (jumps, turns, lots of arm movement, etc.) What are your thoughts about all of the above?

Looking forward to your replies. Thanks in advance!