John‰]

wrote:
Do any of the liquid/crystal drain cleaners live up to their
advertising hype for periodic drain maintenance?

I live in a 1962 house with a sometimes cranky kitchen sink drain.
It's more of an annoyance than a real problem. I remember "Once in
every week; Draino in every drain".

Are any of them worth the money or is it just propoganda?

Kitchen sink drains respond pretty well usually to periodic hot water,
because it's usually greasebased; what I do is let the hot water run
full blast while the kettle gets up to boiling, then pour the boiling
kettle down the now preheated drain, then follow up with more hot tap
water for a while.
Bathrooms are more of a problem because you can't melt hair as easily,
although this will clean the congealed soap and toothpaste out.