It works so well!
I used this in a stainless steel carafe, which had a year's worth of residue left in it.  The opening of the carafe was too small to clean with a sponge or by hand, and there was no amount of soap and water that would remove the coffee stain/build-up.  I let this product sit diluted in the carafe overnight.  After a quick rinse in the morning, it looked like new inside.
Rating: 5 stars