For what it's worth, I just made some measurements on my freshly built DCSM (which is no longer a smoke generator -- long story)
It also has pretty massive gain. 1V on the CV input gives a gain of 20dB, so it's pretty impossible to avoid clipping when the CV is 2V or more. What would be a normal amount of gain for this circuit?
By the way, all my CGS108 gain cells distort when the input signal goes below -2V. There's a bit more headroom on the positive end. Is that normal? I've built seven of them (4 for the DCSM and 3 for the VCFQ) and they are all the same -- all using the same batch of transistors.