I have used Note 4 for an year. I did not have any complains or issues with this phone.
First, lets talk about the camera quality. The camera quality of this phone is indeed very good. It record videos in 4K resoultion videos which was sharp and crystal clear.
The battery performance was good and lasted long even when playing high end games. I loved playing Temple Run on this phone.
Also, the audio quality is is very good. Listening to bollywood numbers was pure delight to my ears. The earphones supplied with the box is of very high quality too.