yeah man.. i know whenever i have 2 different drugs im like "man i hope i have like the ultimate drug combo here" but i never do haha. Yeah if you take too much valium it can totally block the whole amphetamine feeling. And yes most times with uppers and downers it can be risky, but in this case its basically a see-saw, whichever you take more of is what you'll feel. the one positive affect i always liked was, your mind is clear and running, while your body is relaxed and heavy. all about preference though :D