To be prefectly honest, the first one I recieved had a problem with the heater.  The heater light would come on, but the heating element did not work.  I sent the vendor an email and they told me to return it for a new replacement.

I recieved the brand new replacemnt very quickly and it works great.  The heater made a very big difference in how well it cleans.  I definately would advise buying one that has the built-in water heater.  I am very happy with the cleaner and the customer service from Shinning Image.