individual string pitch retuning works very well. it is cpu intensive and thus limits the number of add’l instruments/effects. it will occasionally ‘warble’ if one does not watch to maintain sufficient finger pressure.
there is no acoustic emulation option, although piezo’s do sound pretty acoustic-y. i’m hoping this will be a key new feature in mg4.
for 12 string i haven’t tried this but i bet either two hex string retuners in different channels or two copies of mg3hex would give you your choice of open tunings, each with a secondary octave, and at the lowest possible latency.
shame that 3sigmaaudio doesn’t have trials. otoh, $15 is a fair price. the demos sound solid.
this video shows hex string retuning on a guitar strung with all ‘b’ strings:
