Where have you heard good things about it? From the sites where they sell it?
All I can find is complaints of heart problems, problems sleeping, depression, odd taste sensations, constant stomach aches, and nausea.
The only proven way to lose weight is through a calorie controlled diet and an exercise program. Diet pills are very controversial because of side effects, and lack of published studies to show they actually work. It's not even the diet pill that causes the weight loss - it's the fact that you must eat less and burn more calories.