Actually I have read quite some stuff about these cameras, and it's always the camera department which is not as good as the competition

So I'm not sure if a Xiaomi phone would be a wise choice if you care a lot about the camera, but I'm sure the MI5(s) will definitely have a better camera than the Redmi Note 4!
Or you could buy an Redmi Note 4 and with the money you save you can buy a good digital compact camera? Because camera's in phones are always lagging behind toy opinion, to bad Xiaomi doesn't offer compact camera's as that would be a great add to their assortment.