No, bought one and used it for a while. Didn't feel the need for the extra fuel cost etc in the end - the work i do my electric machines are more than capable. With twin vac booster boxes etc i can get the performance i need even at good hose lengths. Heat isn't a problem - i get enough heat to make them couplings hot hot hot!
Sold it and never been more happy with my set up. Very often its all about our own human nature wanting bigger and better all the time.
Funny thing is TM owners will say how fantastic one is and you can't be without one, and then pull off the van an old basic twin vac electric portable machine to do their upholstery jobs!