Now, theres a question.
I use the Valeton mainly at the moment. Its tiny and sound identical to a Boss OC-2. However, I'm a bit of a hoarder of Octave pedals and have a selection of them from classic to modern. For me the highlights include the 80's Pearl Octaver, and original Boss 'Octaver' OC-2, Foxrox Octron 2, EBS Octabass, MXR BOD. These are all great in their own way and cover the analog octave down nicely.