@ Aplenty- I have used CLR and lime-away, and my experiences were not as good as your experiences. Don't get me wrong, the products work very well, but I was unaware that it would react with so many materials.
I used it to clean the reservoir of my cappuccino maker, only to have it tarnish the metal. The reservoir on my cappuccino machine is aluminum, and I didn't realize that the product reacts with aluminum; among other metals. After calling the manufacturer, I learned that the product reacts with aluminum, zinc, cast iron, lead, and some stone surfaces.
The stone surfaces make sense since stone is a mineral, but I was surprised to find that it reacts with so many metals. My advice to everyone is to be careful when using these products on anything other than coated stone, steel, plastics, and glass.