Century 4000/Ninja here. No complaints, but you need two separate circuits to plug it in (with the heat and the suction and the spray it uses a *lot* of electricity).
And I had to cobble together a DIY nozzle that's a little different from the factory ones in order to get things *really* dry...the larger opening of most extractor nozzles leave a fair bit of moisture (like when carpet cleaning pros do household carpets and it takes hours for things to dry completely). OTOH, the small opening of the nozzle that I like probably puts a lot of strain on the extractor's vacuum motors, but no problems so far.