We have almost white carpet that is close to 30 years old now and looks close to new. It has had everything that grand children can spill on it to mud from out dirt road. I have yet to find a machine that will clean the stains. I keep it looking like new 2 ways. #1 No shoes. #2. Clean all stains from the newest to ones that got missed and were older using oxyclean! I have tried just every thing I can think of on one small milk stain that came from a baby bottle. No luck for the longest time. I just now, in the last week been able to finally get it out! I used portable hand machines that I rented, my home Bissell carpet cleaner and scrubbed with a variety of different cleaners on my hands and knees. So now the carpet again looks as close to new as it did the day it was laid. Unfortunately I have yet to find a better way with stains than to just get down on the floor and scrub till it comes out.