I usually don't pay much attention to radio station imaging voices. Most of them seem to do well by their client stations. But a very few just don't work.
I'll start with the station voice for KFKA, 1310 Greeley CO. He sounds more menacing than Darth Vader. This has to be the worst station imaging voice I've ever heard. That isn't to take away anything from James Earl Jones. His natural speaking voice is a huge part of the CNN brand.
But Darth Vader at nearly every break? Listen for yourself here: http://1310kfka.com/listen-2/
Anyone care to add to this list?