All the colleges you have mentioned are top colleges of the country. But PSG College of technology, Coimbatore has better ranking and rating than other. But the placement record is also good for both Thaiagarajar and Christ University.

PSG College has better ranking because of its excellent faculty, top class infrastructure and placement record. Many visiting faculties & guest lecturers are also part of this college. Companies like Tech Mahindra, Federal Bank, Zoho, Wipro, Bajaj, ITC, Goldmansachs etc. Almost 95% students get placed every year in this college.