Never had pure R isomer although a friend has. He said it is very hard to k-hole on and has a more dreamy/out of it but not dissociated feeling to it, psychedelic but less body effects and less dissociating (he said he could still k hole, but needed huge doses to do so). S isomer kicked my ass when I had it pure , was quite a few years ago though back when I first started ketamine. It is a lot easier to hole on and very dissociative as compared to racemic. Other than about five grams of S I had several years ago I have only had racemic though, which is what I prefer.