Yeah the octaver is definitely the weak point with the pedal. Saying that, it isn't strictly an octaver, it's a pitch shift effect so maybe an octave is too far for it (anyone using a transpose function in a DAW will know this). I sold an OC-10 recently and it was a cracking little pedal so it is a shame this part is so weak. Again, as @Al Krow mentions, an analogue pedal vs a digital recreation is always going to be poor mans version.
Saying that, I don't see myself using it for this anyway, and as a preamp / modeller / NAM pedal, I think it's a cracking bit of kit. My only gripe is that the mod effects don't have a wet / dry mix control, delay and reverbs do, but I would have preferred to be able to control how much chorus I add to my sound. Yes, I can tame it with the controls but a wet / dry mix level should really be there in my view.