Can you show us how your favorite hair looks like when rendered in Octane?
For me hair hair usually looks pretty nice when i use the following settings:
IOR - 1.6
If there is a specular map:
Use the transmap in the power of the specular and set its power to 0.3
If there is no specular map:
Use transmap as specular, but now use a multiply of the transmap and the bumpmap as its power, setting the power of the transmap here to 0.3
How the hair looks really depends on your lighting (power, direction) and your specular (specular, roughness, IOR). Bring life to the hair by using the transmap, bump map and specular map in these specular nodes,
Sometimes adding a sheen to the hair will also help (add the color map to the sheen node and set its gamma to a lower value).