Had a pair for a few months. I generally don't use them on the bike, I prefer not to wear anything in traffic or just enjoy the silence on longer country rides - but that's a different argument for a different thread. Having said that when I have tried them it's more of a background noise, like having the radio on in the background so still aware of traffic coming alongside.
I do use them for running with '
Zombies Run!' app. Sometimes miss bits of the storyline though as they don't provide any noise isolation at all, which is really the point of them. The zombies can't sneak up on me without being heard