It is nice to see an article about how to mount a tv; however, I would like to offer up two suggestions.
I would like to point out that if you are planning on running the LV wires inside the wall you will need longer than 6' cords. One of the most important things to remember when using an articulating mount is to zip ties the wires to the mount in such a fashion that the tv can pull out and be pushed back without putting stress on the end of the cable or the input on the tv. Almos every articulating mount I install for client,s requires 12' cords.
My other piece of advise is to not put too much trust in your stud finder. I may be more careful than I need to be but I always find 3 studs with the stud finder and measure to make sure they are all equidistant from each other, this way you can be confident you are actually marking out a stud because you can find a consistent pattern. Finally, after finding the stud but before drilling the pilot hole, I use a very small screw driverthat I poke into the wall on the left and right side of where I plan to put my pilot hole. The small holes allow me to make sure I am drilling into the center of the stud, and not just clipping it.