After many hours of experimentation, I must say that the Poly Effects Hector is not recommended for hexaphonic guitar processing. Sadly, it simply does not have enough inputs! With all 6 inputs occupied by the string signals, there is only one option left to introduce modulation CVs for the various effects, namely MIDI in.
Unfortunately the MIDI handling is buggy at best; Hector locked up several times when faced with 6 MIDI CC inputs. This also requires a CV-MIDI module if one is to use various Eurorack modulation sources. All in all a very disappointing experience.
Other concerns include lack of switches to enable quick effects bypass and no ability to cycle through presets. Some effects result in high CPU demand and it becomes impossible to use 6 of them in parallel.
The good news? Hector would be fine for stereo processing and the end of the system chain, with 4 inputs dedicated to modulation control. Now what can I put in its place?