the koss will definately fall off your ears when jogging.. i used them, and when i run after the bus, they fall off my ears.. they are fantastic though.. but just not for jogging.. also after a while, the ear clips sorta cut into the top of my ears.. sorta hurts... the sennheiser mx 500's are good.. well i like them.. they can be had at
newegg for $19 shipped.. they sound pretty good, and they're earbuds, so they'll stay in your ears.. and they're comfortable enough to wear for long periods of time