I am using this phone for almost 10 months belive me you will not get such a phone under 12k and its have 3 gb ram 34 gb inbuilt which you can extended by using memory card but you can have 2 sim cards or 1 sim 1 memory card at that point it lack but 34 gb is quit enougf.
The performance is quit good but the rear camera where its lack it doesnt have auto focus feature and the camera quality is average but front camera is good.the phone get heat up at some time but by using back cover you can manage to handle it but its a good phone at 12k
Good work by xiaomi