I have been dead for 30 years because I used an unvented 8,000 BTU Olympian heater so my vote doesn't count.
I figure I didn't need to heat the canned peas, water pump, converter or silverware to I placed the heater where it would be the "nicest". Where it could heat the bedroom and bathroom area.
A FANTASTIC FAN "Endless Breeze" will push the air around the rig with plenty of vigor to heat the whole enchilada in the morning and not wrinkle the batteries doing it.
A FIVE WATT 12 volt computer fan placed on the overhead right above the heater is plenty to push heated air down and mix things up.
Hope This Helps