[MzPriss]

When faced with similar choices, I went with the tent heater. Used it for years and it's never let me down...well, except for this one time when it rained for 12 hours straight near Mormon Lake...but that's a story for another time.

[Maddogjeeper]

Heaters are good but can fail or run out of fuel; a good bag is always warm unless it gets wet but then some synthetic insulating material can still retain 80% of it's insulating value when wet.