the diastereomeric mixture which (9R,S)-HHC is surprisingly has very distinct effects vs D8 and D9, for example a much stronger “couch lock” effect than D8 as well as markedly reduced tendency to produce paranoia as opposed to D9.
between those who tried it, many agreed that there was some sort of “tunnel vision” as well as a variety of other visual phenomena - not unlike those of shrooms - that were of varying intensity interindividually and seemed dose dependent.
one of those individuals took a pretty heroic dose, which - despite their ridiculously high tolerance to D9 - kept them “tripping for 6 hours straight”.