Alright guys I've been reading every thread I can find on this subject. I am either going to buy a AR already complete or try to put it together my self. Problem is I'm a complete newb to the AR platform. So bear with me please. I was wondering if anybody has a piston driven riffle AR and are they happy with it? Any problems? Any regrets? I going to use this gun or guns to try to protect my family and property if the SHTF. My concern is what if gun oil becomes hard to find, it's my understanding the standard AR needs to be ran wet and cleaned often. I don't know if you have to oil it before each use if you have not fired it after a period of time in a vault. Any one that want to straighten me out please do so. I just am a little worried about accessibility of supplies if I run out. Thanks in advance guys.