So based on the promised beta, I decided to take the leap and order a Manther, however, it's not staying. Synth firmware was updated to 1.2.
First, for those curious, look at the spectrogram of the slider sampling - you can clearly see the stepping in the waveform while opening the fully resonating filter and see that it is smoother, but not smooth, coming down.
However, I don't believe the sampling issue is just on the VCF - it's just the most noticeable. If you see my second screen shot, look at the fundamental - everywhere you see a horizontal line in the fundamental is when the volume jumped as the Manther picked up the next value as i increased the amplitude of the saw.
Next, the filter doesn't open all the way with the VCF control seems to open to about 13-14K - I have never worked with an original 101 or 202, so I don't know if this is faithful to the original or not, but if you look at the spectrum of a high note, you'll see the bottom half of the spectrogram is missing harmonics with the filter all the way open until I activate the key tracking.
Finally, it seems most of the sliders don’t actually start affecting their parameters until at least 20% up their range which means that I don’t get the full range of the slider.