There cannot be a perticular factor based on which one can predict that whether the college is good or not. I can give you some of the good features about the institutes mentioned above and the choice would be yours.

Madurai medical college is known as the southern hotspot and it is easily affordable for thepeople from various places. It has a good campus life and the atmosphere. Also you can find the decent teaching there and good numbers of professors and you can have the good amount of the patients to have the practical exposure. Also seniors and the faculties are very helpful and the campus life is also involved in the extra curricular activities also.

Omandurar medical institute has a good campus with decent infrastructure. The institute is located in the heart of the city and you can be very comfortable in the campus im terms of the space. It has a good library with the good amount of books. Also the faculties are well experienced and trained professionals. It has the facilities of laboratories too with well maintained conditions. Also the laboratories have the specially trained assistants for the better guidance. The hospital premises is also good with the reasonable patient inflow for the better exposure.

Chengalpattu college has the biggest campus in tamilnadu which is about 50 years old and the atmosphere of the college is also friendly. It also has the hostel facility for both boys and girls. The professors are very friendly and majority of the professors are the allumni of the institute. The support of the seniors is very good and they are very helpful. The institute has the good cafeteria also. You can get the exposure of the medical field in the college with the hospital and also the institute is highly involved in the extra curricular activities. This institute is not the bad option of all above.

Chengallpatt is better. The college has a wonderful atmosphere. With about 250 acres of land in hand the College has one of the biggest campus in Tamil Nadu.

Pros:

It has a beautiful campus for people who like enjoying natural beauty.

Freedom - The college gate and hostel gates are never closed (for boys) . It means you can go out and come in anytime you want. No one will question you.

Friendly professors and staffs.They make the student's burden lesser.

Most friendly and caring seniors.Also antiragging rules aren't needed in this campus actually.

New cafeteria has started functioning recently, so you don't have to worry about your sudden hunger chimes.

Also the hospital also provides you a large number of cases to look on to and increase your experiences on subject.

Not to mention about sports and cultural activities. The College has well known proud teams for basketball, cricket, football, volley ball, badminton, table tennis, throwball etc.

CHEM fest & CHEM sports - The grand inter college fest and sports meet conducted by the college which is one of the most famous one in Tamil Nadu.

College has a students run mess which provides you quality food with wide variety of food items in hand.

College council and hostel council- provides you a chance to learn improve your administration skills and chance to know more about the college.

The complete amount spend for CHEMFEST and CHEM sports are collected by the students by finding various sponsors from chennai and around.

CHARMS - One of the major academic event of the college which is followed by students all around chennai. Provides you with a lot of options related to academics.

Library : The college has a large library for reading and research purposes. AC reading room and WiFi facilities are also availabe in the library.

CME : Various department take an interest to conduct CMEs regualrly in which you will be able to geasp about some basic and few advance medical knowledge .

More than all these , this college provides something interesting for all kind of students , the studious type, the enjoying type , the sports type or any.

hope you find it helpful

thanks

good luck!