It's Saturday and I just spoke with Greg. I emailed my questions to Corte Clean and Greg responded within the hour. He was great and answered all my questions and then some. I have a raised MoistureShield deck with metal spindles that's 10 years old. I live in Colorado, so don't have the mold issues, no big trees near by and I don't cook on my deck, so no grease stains. I just have dirt and dust from all the wind. I wanted to know if Corte Clean would be ok for my deck? MoistureShield only advised not to use anything containing bleach, but no specific cleaner. So Greg basically told me Corte Clean would really be a bit overkill and suggested I could use RV or Car cleaner, as he is familiar with MoistureShield. I think this shows that this is a very reputable and honest Company. I kind of wish I needed their product and would advise anyone in need of a composite deck cleaner to give them a call. Particularly in the midwest, south, and eastern United States where humidity is generally high. Before I retired I was in purchasing for the industry leader of heavy equipment, so I dealt with many salesmen over the years. I would have to put Greg at the top when it came to customer care.