Disclaimer: I received a sample as part of my JackedPack to review for free. As always, all opinions are my own.
I actually really like this pre-workout verses all the others I've tried. Granted it doesn't taste all that great but who cares if you chug it. It gives me lots of energy to get through my workout and actually a bit beyond, with no crash at the end. I like that it's non-stimulant based so I can still have a cup of coffee after my workout, and not worry about a caffeine overdose. I got a nice pump, and felt like I was flying through my weight-training. The label says it kicks in after about 15 mins, but I think it's closer to 10 mins at least for me. I love that there are no side effect, I didn't get any of the itchy, tingling or sick to my stomach sensation like I have with other pre-work outs.
I do wish Nitrosigine had more information on their website though. There's a lot of scientific gobbled gook, but not a lot of just basic info. I found a couple clinical studies, but it was much the same. Basically this is safe and already in many pre-workout products already. It is considered safe by the FDA. Sadly from my research you can't buy this by itself, you have to purchase the pre-workouts it's in to get it's effects. I'd really prefer to see this as a product by itself and without the added caffeine. If there was more information about this product and I could get it as I have sampled it, I would absolutely purchase this.