Upload & Sell: Off
I've been using these for the past year and a half.
They work pretty darn well, I do get some crossover sometimes when I'm in the city or near anything remotely industrial. For instance, shot a wedding right across the river from the Port of Baltimore on Sunday and they were going freaking nuts all night. Couldn't find a channel that would work at all without crazy interference. The only time it's been that bad though.
They have saved my butt quite a few times. Earlier on in the summer, we had a wedding in an old Catherdral in Philly & my 2nd photographer was shooting the entrances into the church, bride coming down the isle, etc. while I was up in the choir loft shooting down with the fisheye. Right before the processional his camera crapped out and had to radio me down to shoot the entrances. There's been times where I have had the bride and the groom out at night doing some night photos & something stupid like I forgot to change mem cards and I needed one, or I wanted a different lens that I didn't bring out. Also, helps incredibly when setting up first looks & the whole "we can't see each other before the ceremony" thing.
As for the ear pieces, people actually get a kick out of it. We play along with the secret service jokes, it's definitely a talking point, especially with the guys, they eat it up. I've had people comment on how "professional" it looks almost every wedding.