I went with "Pitch Shifting/Octave" as it was my first "quality" effect after a throughly crappy Boss BE5B multi-effects (a DigiTech Bass Whammy), the effect most consistently on pedalboards of mine throughout the years, and something I own multiples of for different reasons: the "SubWave" down-octave on my SWR Mini Mo' preamp that tracks like a mofo and can go from synthy grit to digital clean with a turn of a knob, and my Micro POG that I use primarily for up-octave and "Virtual 8 & 10-strings".