I remember reading about it. And there was an article on the net. But, I searched for it last night. And couldn't find it.

If I do find it, or stumble across it again. I'll post it.

Some customers swear by them. A few swear at them.

They suffer from the same flaw as any central A/C. They work best if they are sized right, installed right. And the customer is informed of what to expect from them.