I done 160KMPH on my Kia classic. Allhumdullillah naver got a ticket 
@qwertypoiu
they add the amount of fine in database with your vehicle no your e-tag balance will be deducted when you getting out from motorway. as the person said who stick the e-tag in my car.
Yes e-tag save money too. once i travel from Fsd-Isb-Fsd. i start my journey from Fsd where the light is off he said i noted the reg no of your car you are able to go. I leave for ISB when i reached there he said sir light is off here. I am opening the barrier when you returning back charge it. i said okay. My stay in isb is just for 3 or 4 hour. I reached on motorway again for going to FSD. it was early morning and the charging office was closed he said sir go and pay the money on fsd toll plaza. when i reached there they have only one record of mine so i save 150/- Rs
of one side don't know which side.

yes it saves money.

P.S>>> My balance was 0 before starting the journey 