∆8 THCO is a somewhat stronger ∆8 with all the tolerance and other caveats. Very meh.
∆9 THCO is quite nice. A delayed, long lasting, pleasant, high. I mostly ate it due to talk of if forming compounds bad for your lungs when smoked.
Since there is a delay even smoking, eating it took hours to kick in and gave a nice high the rest of the day.
However, tolerance was an issue. A few days with THCO and flower didn't get me high anymore.
I think the long lasting effects are part of the reason for that, same as Methadone raises opiate tolerance. Also, I thing any THC or analog without all the other cannabinoids will raise tolerance more quickly.