Given that muscimol (from fly agaric) acts through GABA receptors, it's not too far off that the Z drugs were indeed selective GABA-A agonists (benzos, being positive allosteric modulators, rarely ever induce hallucinations). At least I'd say they are a kind of their own, unlike either delirants (besides one 500mg benadryl experiment which didn't cause any delirant features, I didn't touch that drug class, but love to read trip reports), dissociatives (which aren't hallucinogen at all to me, only at high dosages some black'n'white CEVs) or psychedelics. There are some similarities to dissociatives but the visual aspect is very different.
I liked pagoclone, even when it was kinda underwhelming. Zolpidem doesn't even help me falling asleep but showed some weird stimulatory effects next to the obligatory GABAergic disinhibition. Zopiclone is the most bitter substance I ever encountered, it's strong enough to cause taste disturbation just from the tiny amount which reaches the responsible nerves through the bloodstream. Has some interesting CEVs but I always forgot all because of retrograde amnesia and it usually required alcohol as a potentiator for the CEVs to set in. Can't recommend that combo.
I was on zopiclon 7.5mg for afair three months and stopped cold, no withdrawal to speak of. Benzodiazepines, ugh, if you ask me they are anything but clean ... yeah, at first they feel clean, but made me to do some serious shit and then didn't even calm me down but the opposite. Engaged in a fight for example which I never would have done while sober. Here zolpidem or pagoclone are more clean imo. Out off the benzos, alprazolam might be the best, and lorazepam is a pretty dirty one (which where I lived, psychiatry loved and thus repeatedly used it).
But intolerance - I'd say depending on what sort of. Not to have good reaction to BZDs doesn't have to say that Z-drugs won't work and the other way round. Even if one has done bad stuff on one category doesn't have to mean that the other one is useless but I'd say if this is the case then great caution is warranted. Allergic reactions, the molecules might be too distantly related as for the immune system to recognize them but I'm no expert on this topic.
