Just one?If you are 'prepped' at all you won't be stuck with just one, you'll have asmany bases covered as possible. However, for the sake of the question, I preferthe M1A. Several reasons; the rifle is very reliable and accurate, thecartridge is one that can put food on the table and defend (applies to all .308rifles), greater range than the carbines, and I love the iron sights. But that’sme, I can hit with the M1A and that's the most important part. If you can't hitwith what you got it's just extra weight to carry. If what you can hit with isa .22 hand gun then that is what you should have. There are all kinds of goodpoints to be made for this firearm or that one, but hitting trumps them all.