I LIVE IN THE SUBURBAN PHILA AREA AND HAVE HEARD SOME  WONDERFUL THINGS ABOUT THE RAINBOW VACUMN CLEANERS, HOWEVER I CANNOT FIND ANY INFORMATION ABOUT THEM ANYWHERE. IF SOMEONE KNOWS ABOUT THEM, APPARENTLY THEY ARE USED WITH WATER, I WOULD APPRECIATE ANY  INFORMATION YOU HAVE. THANK YOU

Cameron is very correct about the Rainbow not filtering satisfactorily. I've researched the Rainbow and found out it is very over priced for what you get. The machine has to be taken "very" good care of to last and get your moneys worth. The motor in the E series is no longer repairable and must be replaced as a unit. So the motor costs like $300.00+ to replace, plus labor. This machine is good for certain tasks, especially wet jobs like spills and carpet cleaning. Other than that, the machine just doesn't have the suction and air flow for deep carpet cleaning. If you do purchase the machine, you must be very careful to "always" thoroughly clean the reservoir and separator in addition to leaving these parts air dry completely, unassembled. This helps prevent the motor parts and bearings from coroding. The other important thing is to frequently replace the water at least every 15 minutes of cleaning. If the water becomes too dirty, mort dust and debris in the form of "mud" will travel into the fan and motor of the machine, causing premature bearing failure. It is true that the newest Rainbows have a washable HEPA filter that is located after the motor exhaust because Rexair knows how much dust actually escapes the water and goes back into the air. The problem is that the filter doesn't protect the expensive motor parts and clogs relatively fast.
 
Like I said, the machine is good for people that don't mind the constant care attention this machine requires. I think I would get tired of "always" having to go through this procedure and postpone vacuuming because of it. The thought of always having to break down the machine after every use would deter me from wanting to use it.  
 
The biggest thing I like about the machine is being able to "see" how much dirt one is removing from carpets and gives you an idea how much dirt is "hidden" in your carpets. Another good thing is being able to retrieve things you sucked up that you shouldn't have. Just remember one can purchase a good canister power team that will out clean, out filter and out last, for a fraction of the price of the Rainbow.