I would strongly recommend the ph@rm@ version of this sold by Rus v3nd0rs (especially Ruph@rma/N00tr0picsB@se, can't go wrong with them), which while higher-priced compared to the bulk p0wder type, is fairly cheap compared to other ph@rm@ceut!cals in the same category. Never done me wrong. According to my research, there are a lot of problems with tolerance, dependence, rebound, ill health effects etc etc if you go above a certain d0se with this one anyway (and that ceiling is MUCH lower than most people seem to think it is), due to certain ph@rm@c0log!cal/ph@rmac0kin3t!c properties it has AFAIK. Purity issues aside having ph@rm@ t@bs makes it easier to stick to a known and lower amount each "reading session".
(Tangent but IDK why this one's still commonly classed/referred to as a n00t, either. It's actually a g@b@p3nt!n0!d, and while those are wonderful compelling "reading material", "smart reads" they definitely aren't--quite the opposite to my knowledge and in my experience.)