Does anyone use height channels?

[acritzer]

Originally Posted by ReverendSlim

I'm using height channels. Most of the time, they just make the mains sound like they're floor to ceiling, giving it a very full front soundstage. But when there is a non-directional ambient sound or a flyover, DPL-IIz Height does a pretty solid job of giving the sound some vertical placement. It's a nice addition.

So, you think it's worth it for about $100?
Also slightly concerned about placement. My idea was to simply place them atop the shelving sections of my entertainment center. This will probably have them high enough, but I've read that they shouldn't be place inside the L/R speakers. This placement would have them just barely inside the L/R.