no2 works for some and others personally do not like it. As far as raising levels 950 or whatever perecent, everyone is different and can react differently. the only way to surely know is to try one. try one, if you dont like it dont use it.
side not: mri's no2 black, is fucking ridiculously expensive, and i dont think you should pay that much for an NO2 supp.
I agree about the cost thing, that's the only reason I don't want to buy it. I have a friend who works at GNC and gets me his discount, but it still isn't worth it for me. I was thinking about trying black powder because I've read great reviews on it.