The way I see it with a high end porti is that with a lower flow rate but with a V2 heater mate or equivalent and superior vac than your normal 2 vac machine then you'll get just a good a clean but may take longer to do (forgetting any set up set down debate) infact if you have a super heated system with some rinse detergent in the tank you could even get a drier carpet as you should be picking up more water in a linear TM flushing competition.
Trouble is with 3 vacs a 500psi pump and a heat exchanger how many plugs are needed?
Over to Roger
Shaun