I did not realize this was a myth, but to the extent it is I'm glad it is being addressed. Everyone I know (mostly US midwest) who has one can't say enough goo

I did not realize this was a myth, but to the extent it is I'm glad it is being addressed. Everyone I know (mostly US midwest) who has one can't say enough good things about them. The main barrier to more widespread use seems to be upfront costs for a a new installation, not concern for efficacy.