Somehow using global ROM, the battery is very consuming, 1.6gb RAM is consumed by MIUI. Maybe one of the reason is I on 4g the whole time. However, it's understandable that global ROM has been removed from MIUI website because its not stable, I guess I should flash back to MIUI China first. And one thing, the battery charging is superbly fast, though it's kinda hot when charging.
I tried using both my Mi3 and Mi5 camera in my room with low lighting. My Mi3 appear on my phone as pretty bright, but Mi5 more to yellowish, don't understand why.
Fingerprint scanner is fast and easy (though its not exactly convenient for the need to press the home button to activate it.). Phone is light and nicely curved, the sides design is similar to Note 5 though

White colour looks very nice and clean, hope i doesn't scratch it that soon though I already put a case on.
Overall, the phone is pretty good for me now. Take note that it's a budget phone to begin with, don't compare exactly with S7 or Iphone and you're all good.

I think because someone mentioned that miui will keep trying to connect to my server. Will need to disable it/sign out then the battery life will be good.