I've had a Powr-flite perfect heat machine for nearly 2 years now.
coupled with a wonderwand, and Cfr handtool it is a very capable
machine. Mine has done a LOT of work, including 3 schools each
August, which is 10 days of solid slog.
In this time i've replaced 1 vacuum motor, which was ruined when
a pinprick leak in the perfect heat coils soaked it, the eccentric cam
on the water pump, (which has never leaked), and one of the thermostats
on the water heater. The vac' motor brushes are still within service limits.
The regulator on the water pump is not correct, as mine goes to 700 Psi
instead of 500, ( It's a 1000 Psi regulated down ).
I've thought about a Scorpion, but the lack of heat puts me off, and the
drying times on my machine can not be bettered by much. With the machine
and wonderwand combination, you can clean at maximum pressure, and on forward
strokes as well as back if you wish. So you can clean very quickley if you have to.
So as far as i'm concerned the only possible upgrade would be a truckmount.