Hii,Hands down RNSIT if you are looking for ECE/CSE and also ISE to some extent. 

In every way RNSIT is superior to the other mentioned colleges in terms of acedemics, faculty, student quality (except a few, who are not worth mentioning. While some are however exceptionally good also), placements and technical exposure. 

Not sure about other branches, because honestly Mechanical, Civil and Instrumentation sucks here

Mechanical is however better among the 3 branches mentioned above since it is older. But with only 2 passout batches, Mech students still get placed at IT mass recruiters.