OK, first, I am 43, 6 feet, 236 pounds in morning, and stay 5-7% body fat, bodybuilding since a teen. My test of testosterone in blood this year 2018 was 735ng/dl, so for my age in higher end of normal range. I usually do not have much problem in the gym. As a teen this was in all the major bodybuilding publications, sating things like "Increase bench by 8%", "More Endurance", etc. People used to call it "Orange Crush", because they could crush their old records on it, and it crushed your body in a good way. I wanted to try it out! What surprised me, is that there is protein in it! Which makes for a great pre-workout, a little protein cannot hurt! I have always exercised on a full stomach anyway. I followed the directions, and in about 30 minutes I felt very warm, and like more blood was flowing everywhere, including my head. It made me want to lift. I am no expert on why it made me feel this way, but, it seemed almost as if a pro-hormone to me. I have limited experience. I easily could lift what my goal was in the gym for the day, and easily added two sets for no other reason than I was not tired out like usual. So, this really does what it says in my experience. Again, I took this while taking no other supplements at the same time. It is not super super powerful, that if you are already taking a lot of supplements that this will overpower them would be my guess, but certainly there is some energy/focus added by taking it. Even after the gym I felt that it might have some fat burning properties. I definitely recommend it alone, but would not take it with any caffeine. It is strong enough by itself. That is my experience. I do not remember there being DMAA or DMHA in it back in the 1990s. I looked for an old advertisement and it did not say either of those ingredients. It is also lower price now, because the same size bottle was 59.99 in an old paper catalog I have. I prefer this to a super strong pre-workout powder, because no jitters after. It assisted me in my workout and pushed me further as advertised. So instead of 4 rounds of push-ups to failure, I could do 6 rounds to failure. That is "as advertised" to me! Just read the description, and maybe try half a serving to start if you are new to it. Just be careful. Do not go overboard, you do not need to with it. It is very strong by itself.