While I'm just getting back into backpacking, I do have a lot of experience with MRE's. I would think that because of the weight, they might make a good first nights meal. I wouldn't carry them around for 3 days before eating them. Save the freeze dried for later in the trip. It just seems to make more sense to lighten up the pack as soon as possible. The heaters work better in warm conditions. If you're planning on using them in cold weather, you should keep that MRE pouch close to your body to keep it warm. Taking a 40 degree pouch and sticking it in that heater often just makes a luke-warm meal. I've heard all the alternate meanings for "MRE" and I think they're all great. Some are really good and some are just disgusting. I had the chili not too long ago and it was delicious. The maple flavored ham slice on the other hand isn't fit for canine consumption. No really. My old beagle wouldn't eat more than a bite or two of it.