I thought it really helped me, in calming down that part of the brain that produces the cravings. My thoughts while taking it seemed clearer. I was always told though that I should use it in combination with a program and/or therapy. The cost can be high if you're not covered, and there can be side effects. I had some but not too severe.
People can have their own reasons for and against anti craving medication, it ultimately comes down to the individual in consultation with their doctor.