Whichever of the two you manage to convert will be best for you without any doubt given or taken few factors like location, infrastructure, rankings, and others. On a more serious note, TAPMI has a more heterogeneous and diverse batch of students as compared to BIM, which has a certain number of seats reserved for students of Tamil Nadu.
In terms of Placement, both are more or less on par, though of late, TAPMI has seen companies from various sectors (including e-Commerce) placing students with packages crossing the 7-digit mark on a regular basis.
In the end, everything boils down to you opting for which college. After all, after graduation investing one or two more years is quite worthy if it is from a good college.