I guess I'm conflating two different issues. I don't personally care for using an octave pedal to emulate a bass guitar sound (or, shifting a bass guitar down even further...) But for that purpose, you'd want something with a "clean" sound.It definitely helps the LED and silicone modes, I get a pretty convincing blue beard on silicone/high gain
Meris Hedra can do pretty good, if you don't mind the digital mess. I know the SV/SVD isn't clean but it sounds clean when mixed nicely with the, well clean channel. Is that what you're after, straight clean tone, one octave up?
EDIT: nevermind I see, you don't like having to play higher to get the lower octaves to come through clean? if so that's just how it is, gets so low it begins to move to slow to hear or be clean
My only real use for octavers is textural. So the SV/D sounds like a good proposition to me, given that I don't have to shift playing positions to get the synth texture I want. So really, *I myself* do not want clean.