I read a lot of post about how AR's are inferior guns due to the fact that they are DI driven and sensitive to dust. Here is a little proof that you shouldn't beleive everything that you hear. But, you CAN believe what you see.
BTW im not knocking AK's. They are good guns. Cheap, but good.
With all the piston talk about AR's and the DI system being dirty.... you should check out this post by Nutnfancy. Granted the video is a bit on the long side, and it seems the price of piston conversions are coming down, but he shows that piston guns have thier problems too. I know that my AR gets a little hot in the lower reciever, but I personaly would rather have the heat there than on the handgaurd.
I guess that is one problem of having a "big ol' metal quad cool rail" on the forgrip.... Handy... But hot.