Although far from non-existent, none of the chemicals you list are more ubiquitous than acid nor usually sold as acid. Actually, their effective dose range is a

Although far from non-existent, none of the chemicals you list are more ubiquitous than acid nor usually sold as acid. Actually, their effective dose range is about 100x that of acid and it would be hard to impossible to fit them on a tab. NBOMEs are something you did see sold as acid especially a few years back, so I'm not saying you shouldn't be careful. The difference in effect is fairly easy to tell, though, and I have no doubt most stuff sold is the real thing. There are some closely related and nearly indistinguishable compounds, but as far as I know, they are about as hard to synthesize and should have a similar risk profile as LSD.