I could not imagine eating a MRE without the heater. I know alot about those things. I am in the Air Force currently serving in Iraq. I have had more MRE's than I can count. There are 2 types of heaters out, the old and new kind. The old kind is one solid heater and theother is a bunch of heaters all together. I really wouldnt worry about the smell since you should be outside. Eating something like Hamslice or beefstew would just taste like crap without the heater. I recommend MREs because it is loaded with calories for energy to burn of in the field. Also is great for your muscles since normally each meal is loaded with over 22 grams of protein. Last but not least, they do not cause a fire of any sort. Take it from me I have tried to light things on fire with these things,it doesnt work. The only fun thing to do is to play aprank on your hunting buddy is put an unused heater in a 20oz bottle and put some water in there. Then throw it behind him and watch it blow up. He will jump right out of his camo. Good Luck Hunting

Mathews shooter for life
John 14:6