Boss OC-5

I saw Mike Dawes lauding this pedal, and thought I might have use for it. Had to wait 3 months for it,(Covid times) and was slightly disappointed.
I got this pedal to have a bass tone while doing Acoustic fingerstyle blues/rock. I use a passive soundhole pick up.

In poly setting, it always plays the lowest note, and that means any note, so it can happen with syncopated style,you get the occasional unwanted octave effect on a higher note. Since I play stereo and always have a clean tone on one channel, it does not bother me much.
It tracks very well, just dont use a flanger or so before it, because it will confuse the tracking.

It has a lot of features that I have not used. I did try it on a baritone electric guitar, sounded impressive.

Con: the octave up sounds not pretty.Somewhat distorted. But I´m sure a creative rocker can do something with it.
It takes some time to get used to turning the knobs to get it to work the way you want.

I wanted this mainly for the new range feature as it takes the lowest note of a chord and adds the octave effect. It works as described but took me a while to dial in the mix.

It should be noted that when using the range dial, anything above the "lowest" region will apply a filter so that the octave effect will not trigger on any notes above that filter. When using the "lowest" region, it applies it to the lowest note/s of a chord. It wasn't entirely clear that this was the case.

Tracking is excellent, occasionally you can hear it struggling to latch on to notes in large chords.

I recently started needing an Octaver so pulled out an old Arion Octave pedal from the 1980s that was languishing in the gear cupboard. It worked fine and it made a good sound. But I'd always wanted an OC2 so after reading the reviews I ordered the OC5... Wow! This is so much better than the old Arion. It has a big confident sound and excellent tracking.

I'm preferring the Vintage (OC2) mode over the Poly, and as I'm using it on bass the -2OCT knob stays set to zero. I didn't expect to like the +1OCT but a smidge of that added to 50% Direct and 30% -1OCT makes a huge fat sound with added clarity. However, if you want the Guy Pratt signature OC2 sound that's just a few knob tweaks away.

Thoroughly recommended for bass and well worth the cost.

I use this pedal for my acoustic set and blend the octave signal separated from the dry signal to enhance the overall mix.
I basically use it like Mike Dawes does (minus the crazy skills) with the threshold targeting the lowest strings (not lowest note mode).
If anything check his rig rundown to understand how to use it, he says it all and demonstrates it like the master he is.
I don't use the lowest note mode as it would require me to turn off the pedal when only playing high notes and I can't be bothered.
Strong build like every Boss pedal, sturdy, silent, does the job and that's all I was expecting from it.
Very happy with my purchase!