I decided to try the ephedra free stacker because I have had insomnia not so long ago and feared it would trigger it again. My main motivation for using stacker 2 was to loose feelings of hunger and get a little more support during weightloss. When I first took the tab, I took it with breakfast, so I could note the effects all day. After an hour I began to feel a bit more energetic and felt like doing things, just the same effect any energy booster gives but in a subtle way, not like I wanted to go for a jog. It never really reduced feelings of hunger, just for a couple of hours I'd feel 'satisfied' but then the hunger came back, can compare it to a good meal. Overall I can say as a mild energy booster stacker2 is very nice, I never experienced bad side effects, I never felt nervous after taking it. Well I never tried taking a higher dose because I dont see the point, I wouldnt want to risk getting used to it I wouldn't recommend it for weightloss, but it is a harmless product.