I was a bored housewife who went to finish my undergrad degree. While in school the past year I waited for my husband to start cleaning the house. Never happened. In my silent protest I only cleaned the shower well only a few times this past year, so busy with classes and an internship and kids. I Just graduated last month and began catching up on cleaning; the shower, however, was a MESS! Hubby promised a housekeeper once I finished my degree and started working. Hooray! Now I am really worried he will change his mind once he finds out how easy it is to clean a filthy shower with this new product. I thought my glass shower walls were ruined forever with soap scum and hard water marks, I have had shower doors in other homes that were impossible to get hard water spots off - not if I had this product 10 years ago! I was truly amazed, and I rarely take time to write positive comments on products or services.