Okay I will check out Diatonic first. You gotta be joking though?? They charge this much for a stereo pedal and then only make some of the algos in mono!! That is insane! I sold my Digitech HarmonyMan for this pedal because people told me the Pitchfactor would do a better job of harmonies and I always play in stereo with a pair of old Fender amps. The HarmonyMan split the harmonies so they were in stereo and sounded more like two separate guitar players. I you used three part harmonies the main note was down the middle with the two harmonies split in stereo. I am already disappointed and don't even have the pedal yet 🙁
What about QuadraVox . . . . . is that in stereo?
Just to be sure we're on the same page, "monophonic" doesn't refer to mono or single channel, rather it means that the algorithms do their pitchshifting, or pitchtracking to create a synth voice, on monophonic or single note material (as opposed to chords). Most of the algorithms in Pitchfactor do stereo effects when hooked up in stereo. The exception is Octaver, which pointed out above, is dual mono.