What are people's views in using a cffeine supplement to reduce fat levels and improve energy levels when working out?

I don't have a problem with it. It is a stimulant so does help with your energy levels. Just make sure you have good energy source in your body to burn otherwise you could be burning muscle. I've also heard some people complain that some of the caffeine stacks make them feel mean and they crash when they come down off of it but I imagine they were taking it in pretty high levels.