Advantages:
1.M30s having 6000 mah battery which is quite good( it gives you almost 2 day backup).
Try to pick higher variant due to lower variant is not work properly ??.
Playing Games like BGMI(pubg india) , call of duty, free fire , etc smoothly but at lower graphics.
Camera is also work fine.
Disadvantages:
1.My some friends facing battery problem after 1 year of use.
Lower variant not so smooth due to which you have to purchase higher varient.
2hours of gaming make mobile so heat....
If you are living northern side then it might in 1 hour also.
4.Camera updates are there which helps to operate camera feature to use easily.
But after the update it could stop working.