Time and Career Launcher are definitely undisputed institutions. However of late IMS, CATking, Vistamind and CPLC have catched up and doing fairly well. Hope this anwers your question

• Time
• CPLC
• IMS
• CareerLauncher
• CATking.
• CATking hasvery low cost feestrucure and has some best in class teaching material and records.
• TIME and CPLC are well suited for exams like CAT, XAT and GMAT which are intense and competitive.
• IMS has nowadays seen good uptick with its unique way of teaching.

Dear Aanany

Best coaching centre for CAT

1.Alchemist

2.TIME

3.IMS INSTITUTE

4.TathaGAT

5.Career laucher 

6.Mindworzz

7.AnkGanit

These institutes would guide you and all depends on your hardwork to give in your goal.