Focus Speed NEX 5R/6 vs. 5N
I only use the movable focus point mode as I find the area focus to be unreliable. It can focus on an unintended subject.
So my experience with the movable focus bracket is that its a vertical and slant sensitive type and will perform poorly on horizontal lines and if you point it at a focus spot with a horizontal line, it start the "hunting" process.
My work around is that if I can see that the focus spot I want has horizontal lines I will just rotate the camera slightly to make the horizontal line into a slanted line and it will lock focus. This way I can eliminate hunting 99% of the time.
Because I don't use focus assistance light, the 1% failure to lock focus occurs during ridiculous low light conditions.