Of all the octavers I tried (BOSS, EHX, Line6, etc) this Digitech one has the best bass sound I can get out of a guitar by using -1 octave. When I compared it to the EHX Pitchfork that sounded good also but more like a acoustic upright bass and this Digitech has a more electric bassguitar sound I needed.
And the tuning drops, by half note steps, are perfect to: it saves me a lot of half-step downtuning guitars and goes (metal!) down to D and C. Very good sound and very little latency.