Are most folks running diesel or gasoline heaters? I suppose it depends on vehicle type. I don't plan to plumb my heater to my vehicle tank but an external tank located in the flatbed (probably around 10 gallon size up by the headache rack). Gasoline seems simpler since that's my truck fuel and snowmobile fuel for redundancy. But diesel is more efficient. Is there an advantage to gasoline in the middle of winter knowing my fuel lines will be in the bed of the truck? How about high altitude performance (>10,000ft).