Good boost of energy, but unfortunately I find the taste horrific. I've had a few different brands of preworkout before and this one is the worst tasting one I've had so far, so I'd recommend mixing it with juice not plain water. It also has an aftertaste from artificial sweeteners. (It doesn't say on the label what type of sweetner). I find it difficult to tolerate. No side effects though and performs as well as other standard pre workouts I've had. I purchased this because it was on clearance but wouldn't pay full price for it due to flavour.