I think it mainly depends on the flavor of the SHTF situation...
If it's hordes of zombies, then no... you are gonna need a high cap wondernine...
If it's some sort of domestic unrest/foreign invaders type situation... I think it fits the bill nicely...
very concealable...which is important because you won't neccesarily want everyone to know you are armed for various reasons...
Foreign troops are going to be disarming anyone and everyone, so open carry will be out in that situation...
civil unrest will be sort of similar possibly.. you don't want to go wandering around in your mall ninja tac gear including the thigh holster if there are troops or police patroling...
and
In an all out "the world has gone crazy" situation if there are no authorities around and you are on your own it is also unwise to "show your cards" so to speak... as anyone who you run into or happens to see you before you see them will have a good idea what they are up against and will plan accordingly to disarm you for their safety to do what they will with/to you and/or possibly take it from you for their own use...
and caliberwise it packs enough of a punch (with proper shot placement of course) to fill the exact role it was designed for...ie: a last ditch, close range weapon...
also, it is dead nuts reliable and not as susceptable to becoming inoperable if it gets a little dirty due to enviromental conditions or powder residue... trust me, I know both of these for a fact...
I think realistically you should not be considering taking only a pistol into any offensive situation and should be relying mainly on a shoulder weapon for any sort of shots in the double digit range...I mean honestly are you going to be taking long shots with any pistol in any kind of conceivable situation? You shouldn't be using a handgun to shoot at anything you can't hit by throwing a rock at is my opinion...
A friend who is former military has told me on several occaisions that a rifle is a main offensive weapon that can fill a defensive role if need be and a handgun is a secondary defensive weapon and you should never deviate from that mantra or forget it...but he has picked out his zombie killer guns already so take that for what it's worth...
So I think the Mak fills that role just fine as long as you are comfortable with it and proficient in it's use...
I have been known to carry my Mak as a primary weapon and it has it's place for a home defense weapon as well...
With that said, I would not feel like a weenie if all I had for a sidearm was my Mak... I enough 9x18 ammo to hold off the zombies...
I hope...
But if I have time to make a choice I'm grabbing my Sig...