i don't know the answer to your stereo i/o question for your application, but i can say that i bought the pitchfactor after years of comparisons to other pitch shifters because IMO it's the best thing to ever come out in a stompbox format for whammy style effects.
i love the musicality of the whammy 1, but could never justify the price given some of its limitations, and later whammys, while all somewhat cool, were never very satisfying to me. i'd play them here and there, dream of all the possibilities with a pedal that would do what they advertised, but ultimately i was unhappy with the sound quality and tracking on the whammys.
the pitchfactor isn't **perfect** in its tracking but it's the best i've heard, it's extremely musical, and its other settings and features make it one of the coolest things to come out in a floor box. i'm generally not a fan of multi-effects OR DSP based effects. i used the time factor on some recordings and live a few times when it came out but ultimately returned it. loved the features, but couldn't handle the fact that it sounded more like a computer than the analog and tape delays i prefer, and there are richer sounding digital delays too. i still recommend it to people for whom features are the biggest factor because it does sound good, and there aren't many other stompbox delays out there with the programmability and preset memory that could even rival the eventide. maybe in a few years the A/D converters for units like this will improve and those subtle tonal differences will disappear.
for the pitchfactor, while you still get some of that DSP tone with it, because the uses for the pedal or so unique, for me it's completely worth it. add the aux switches or a couple of expression pedals allowing you to control changes to all the knobs with one foot sweep, and the possibilities are insane for this thing. there's nothing like it short of using a laptop to automate all your effects, or having an engineer or someone manipulate your signal for you while you play. the thing is crazy. it does ALL the stuff i'd want a whammy for and then 10X more on top of it. if you're willing to spend the money on a whammy 1, i'd at least demo it against the pitchfactor first. the presets out of the box may not convince you, but spend some time adjusting the default settings and it will open up. i still haven't gotten the hang of mine, which may be one argument against it– almost too much flexibility, but if you have the discipline to focus on getting sounds you like instead of just futzing with it, the thing is gold.
