Why is Metro so buggy?

I don't want to say hacks, because these just look like glitches.

But I have have played Metro all day, and aside from all the rabid sweathogs and flame exploiters, there are two major things I have been seeing:

Stretch Armstrong and Death first shoot later.

I have seen this on smugglers tunnel too, but seen it more often on Metro. First time I saw it. I saw a gun and a backpack float by, and figured it was just another invisible hacker, until the guy came around the corner and his arms were 2-3 times the length of his body and he started ripping me up.
I figured it was a one time tear glitch and chalked it up to buggy game. But I have been seeing it all over Metro lately. Guys were their arms are supper stretched out and they can still shoot accurately but if you shoot their actual body they take no damage.

The other one I have been encountering is that a guy will run into the room and I will instantly die from a head shot...but the guy doesn't fire until AFTER I get the death screen. And its never one shot, its a mag dump. Every time, and this happened in three different games.
And no its not my internet lagging. I have fiberoptic and get 300mb upload and download, I have not had any issues with my internet speed while playing this game, and I only play US east(local) servers, so its not a high ping rate.

Anyone got any feed back on this?