I received two samples of this stuff last week. I really liked it. I'm sensitive to stims and I ordered sample because of their no jitters claim. They're tellin the truth. I had no jitters , when I first got to the gym about 15 minutes after drinking it I had a focused , morivated, uplifted warm feeling through my body. I was smiling and happy for no ****in reason and that's rare for me Unfortunately. Haha. I honestly had a slight euphoric feeling like I was about to start rolling on extacy(and no I'm not tryin to sell it). I didn't get more of a noticable pump than usual that i could notice but my intensity, stength and endurance was solid as hell. I slept fine that night and usually don't when taking a stim product in the afternoon. I hadn't used a pwo in almost 3 years and this was a great first one back. Definitely a good product and I'm extremely picky and critical as I'm usually sensitive to these. I.e. jitters, unable to sleep, bubble guts. This gave me none of thee above. Ill be ordering a tub soon, thanks PerforMax! Feel free to send more free samples to this broke dude;-)