All are the decent college but as per the analyzing report of Careers360 Christ University has AAA rating which means above average and Rajgiri college kochi has AAA+ rating which means good. The rating is based on the research of the college on the placement, faculty & Industry exposure etc. You can check the complete placement of the colleges with the given below links.

St. Joseph Bangalore Placement

Rajgiri Placement

Christ University Placement

You can also check the genuine reviews of the college with the given below links.

Christ University Bangalore Reviews

St. Joseph Bangalore Reviews

Rajgiri college Reviews

Good Luck!