Regarding the potential use of the Chiaphua motors as small space heaters, you may want to go back and read through
this thread for some interesting observations. Within certain limits, you can expect the Chiaphua motors to experience a reasonable degree of heating during normal use. But at some point, "reasonable" becomes "way the heck too hot." The exact conditions under which this transition occurs is not precisely known, but passing the transition point is dramatic and irreversably damaging to the motor.
-dave