Hello Sir. Both courses are good. The choice depends on the person which he/she wants to select. According to placements, ECE is a  much better option than Mechanical though. In government colleges, Mechanical have good placements opportunities. Now the choice is yours to make.

Hey there

It depends on your passion if you are choosing branches just because one branch has more scope than other than that would benefit you as if you'll lack interest in your course then at some point you will think to drop the course which we all know is very hard to. So choose wisely mechanical has its own benefits most of its jobs are field work and for ece it's computer work mostly so this may be a criteria to decide. 

Good luck