I took it combined with some dioxyme M.P.O. in a sample that was given to me. I am a stim-o-holic and am beyond familiar with caffeine, but this was like a friggin mega buzz. Not sure if that could be from the geranium oil extract? I hadn't ever used any of the old dmaa pwo's, but this was something else as far as energy and focus, also had a nasty crash, but tolerable for those rough days when I need the extra push. Anyways, thinking about trying some other of the existing dmaa pre's still available, but wanted to see if anyone else was familiar with this first.