Both cameras are great on the note 3 and s5. I don't know the specs on the note 4, but comparing s5 to note 3, it's all about screen size. I personally don't want a phone that big but some people love it.
The note series has always been a step ahead of the galaxy S series though. So I would assume the note 4 would probably be a bit better specs wise than the s5, specifically the ram and probably the processor speed and series.
If you like the bigger screen, go for it. But I own an s5 and love it. Very responsive, no lag like the s4 had.