I have used the bubble wrap method also & I will put it by the heater outlet of the car for the trip to the field & it stays nice for a long time. I reheat it once in a while to keep it warm for longer flying sections. A tiny squirt of lighter fluid down the carb, or in the fuel line at the carb will fire up the coldest of engines without any heat from a torch. I would hate to catch my plane on fire. This year will be the first in almost 20 years that I will not be able to fly on the first. We moved to N.Carolina in July, so all my years have been in north east Ohio. Many times needing a 4x4 just to get in the driveway. I have used APC & also master airscrew props & they will break alittle more often when cold, while the same hit would not break it in warm wheather. Have fun & enjoy. Bill