I have been using Listerine regularly for about a year and I must say, it really works. I can feel that the mouth stays fresh and odour free till the evening.
Go for the mint one, though it might be painful to keep rinsing for 30 seconds, but I feel it is the most effective one.
A big bottle costs around Rs250 and will last you about a month. I suggest you try every variant and choose the one which best fits your preference.
Use it twice a day and you will yourself feel a cleaner you.