As a professional stone fabricator and installation contractor for more than 20 years, I have used the HMK Stone Care products in numerous projects. The R155 Intensive Cleaner is an amazing product when used as indicated.It has cleaned grout haze and removed hard water deposits on many projects. In one case, a marble shower that I installed 15 years ago was severely neglected. When I was asked to clean it, I thought the stone would need to be replaced. I soaked the shower walls with a solution of R155 Intensive Cleaner mixed with water (1:4 solution) and sprayed the solution on the walls and scrubbed the walls repeatedly for nearly an hour. After rinsing, I was amazed to find that this cleaner completely removed the buildup of soap scum and mineral deposits, and the marble ended up looking nearly new.This cleaner is not intended to remove dye or sealers. It does remove wax and polish buildup very well.I have used other �professional stone cleaners� before, but nothing cleans like HMK R155 Intensive Cleaner. I would highly recommend it for most cleaning. For oil stains and dyes, I would suggest a different product.