They were awesome when I bought the house. How the hell do I clean the water deposits off the glass and the tile now. Not mildew, just lime or watever the hell it is.
Cleaners can work, but you need to be careful, especially if the shower walls are cultured marble. I have this in mine and the hard water in Pflugerville is brutal. Cleaners for this type of cement-laden water does not work due to the harshness it creates on the marble. The best solution is to squeegee the glass off after every shower. We moved to a water softener and an additional filter for drinking and what a difference! I would never go back to regular hard water. We use less laundry detergent, shampoo etc. and the shower walls/glass doors stay clean with the squeegee. The softener is through Culligan and about $46 per month, but do not buy one as they charge for service calls and salt. In renting one, all you do is call with a problem and they come to you first, before others that own.