^But KneelB4Doom is right, weed is clearly the one thing that doesn't quite fit into the list you made. If you had said THC is THC, no argument there, but different weed strains actually have differing cannabinoid contents and differ in their effects accordingly. Therefore weed isn't the same as any other weed in the same sense that LSD is always the same as any other LSD.
As others have said, LSD is LSD. But remember the importance of set and setting, taking LSD as an obscure scientific novelty in the 50s must have been way different from taking it in the late 60s with all the propaganda, good and bad, influencing peoples trips, and still much different from taking it today where we have this huge amount of information about it available. So taking LSD today is not the same as taking it in the 60s, but that is because the environment in which we take it has changed, the LSD molecule is still the same as it was.