Well, in the case of the chopped waveforms, to really know what's going on you need a 'scope.
Witness the following example. Note how the CW-80 with no load tends to have a LOT of ringing on the waveform, this doubtless accounts for some of the issues people report with this transformer.
The last two pictures are with a 2A load, note that the ringing is reduced to a minimal amount, though you can still see it.
CW-80 half throttle, no load
CW-80 full throttle, no load
CW-80 half throttle, 2A load
CW-80 full throttle, 2A load
Contrast those waveforms with the Z-4000