i use maxim on my restaurants, at my house, and where ever there is going to be stuff that has color spilled. tefon for people with pets and children who spill stuff alot, as it gives them the feeling that its easier to clean up if its still on the surface. especially when it comes to pet urine, as it doesnt let the urine contact the carpet backing and absorb in to the latex glue or padding. but of course only works that way if people have small pets not big 1 gallon pissers.
maxim has acid dye blockers that work very well aginst wine and pop, and red stains from food, drinks, and pet throw up. pet food has colors added. and those are quite often the hardest to get up since they come up with stomach acid to damage the carpet.
cobbs stuff have acid dye blockers, hows the dry soil resistance? cobb you have a microscopic pic of carpet treated with your stuff? is it endorced by any carpet mills?