I am using Mi note 4 from last 5 months and what I found was great as
Battery 4100 mAh lasts for about 1 day while roaming
Display is great .
Ram management is great , as it never got hanged while playing high graphic games.
Camera 13 MP camera is not so good but not bad . Front camera with 5 MP is good.
Speaking of sound quality I found it great and loved it .
The launcher I found is not good but you can change it and customize.
As for charging it is very slow as it takes about 3 hours for full charging.