Before its implementation, people made fun of it.
but now, when it is implemented, people came to know how useful it is.
Because of this formula, the number of vehicles is limited as only those vehicles can come on street which are supposed to be. 
2 4 2
i also want speech on against this topic
According to me the one of the drawbacks is that it might happen that someone doesn't have a vehicle with a even number or a odd number.
It is not implemented on ladies too. They are free to drive vehicle with any number. So, we would not get full results of the odd even formula. The size of Delhi is also small so it wouldn't take much vehicles to pollute it.
It would also take long time to control and deplete the pollution level.