A couple situations from the weekend

[Lcubed48]

I have been using them since last season. I prefer to put the earpiece in my left ear. Since I wear hearing aids, I just take my left aid out. It doesn't bother me during play. However, I do unplug it when I'm talking prior to play beginning.
It's annoying to me especially when I am doing the coaches/captains meeting. I however don't force my partner to use them.

I've found them really useful in a competitive match because the exchange of information between the partners is quicker, and you can keep the flow of the match moving. Also, when I'm working with a newbie, I can provide them with instant feedback on their work.