Pretty much the 1st time you take it's ALOT, esp if you haven't taken pre workout in a while..
I got the Sour Gummy flavor and its surprisingly VERY good in taste and effect, I HATE the chemical taste of some of the other major brands and this just tastes like Waterboy/electrolyte power type of drink.
Very smooth and I love the nerds gummies and tastes similar to that to a degree but not overwhelming.
Overall it lasts 2 hrs+ depending on tolerance Id cycle it on and off to keep the effect consistent.
No stomach issues, nothing crazy I've seen just a SLIGHT jitter/itchy/tingles on the 1st day but again afterwards nothing like that just focus, energy, great pump and a smooth ride.