Midi quantisation isn't a reason I would put forward as being important when comparing them. For me it is all about the accuracy of the pitch detection: you can always nashville string your guitar to improve detection speeds, but if low C sharp on the 3rd string sometimes takes 20ms to emerge and others 30ms, then its difficult to play. If every one takes 20ms then you can cope. Of course, the VG unit - by avoiding the limitations of information theory - has a more-or-less constant processing delay so after a while you ignore it.
On midi quantisation: MIDI velocity is indeed restricted to 127 values and - with a suitable modular style synth - you could devise scenarios where you could hear the difference between a note of velocity 126 and 127 all other things being equal. But in the context of pop, rock and even jazz music those scenarios wouldn't be realistic. If it was a problem we would have had MIDI2 by now. Pitch bend - which is much more important - is represented by over 16,000 levels so if you set your range to be 2 octaves - common in guitar synths - then the difference between successive pitches is 0.0014 of a semitone, which is surely good enough.
On expression, if Roland weren't so risk adverse, we might see pick envelope and harmonic content rendered as control signals - they are certainly measurable with modern processing speeds. Axon units can read the distance from the bridge to the plectrum and this is a very useful source of control signals.
But for me I could never replace pitch to midi because synth-like sounds created by waveshaping are audibly less pure than those created by circuitry or calculated mathematically inside a suitably powerful computer. Synthesisers are - in some respects - 'cartoon' instruments. They are abstract in the same way that a drawing is abstract when compared to a photograph. The stylisation and reduction of detail is part of their enduring charm and thus the wave shaping artefacts in the 'wave' and 'brass' processes reduce their impact.
Although I'd love to find out how good waveshaping could get in under 10ms if you threw some serious processing power at it ...
TBF I wouldn't be without either my Axon or my VG88....
Edited by arkieboy (20/04/12 02:19 PM)