IMHO, This isn't a question about One electric TM being more powerful
than another because that can be had by plugging in here, there, and everywhere.
Instead I would imagine its more about achieving MAXIMUM performance on 2 cords from one location (rather than having 3-4-5-6 cords) and able to run a reasonable distance (150'-200') from ones vehicle and achieve clean, dry carpets. Anything greater than Maximum
means more cords, more inconvenience, and hassles.
I know this to be true because I have experienced it going way back to the early 70's.
I wanted then, as Operators demand now, convenience, performance, and as dry of carpeting/fabrics as I could achieve without the hassles of blowing circuits, and/or laying down more cords from one location.
Therefore, there are "options" out there for anyone researching for a ETM and who desires a portable for high-rise and security jobs. That's referred to as: "Versatility".
Best to all;
Ed Valentine