Delta remember most people take 2 caps at then 1 or 2 later on. So it's often 150mg in your 1st dose, but from what I've read the caffeine doesn't make anyone jittery, but instead tends to deliver a smoother sustained energy from anecdotal feedback.
I've just started mine a few days ago, and I got a bit jittery, but that was because I took some JP8 which had more caffeine.