There is one big difference between firefly and superfly which is that superfly follows the conservation of energy rule. Often firefly shaders do not follow that rule and there is over exposure of the highlights, typically from blin or anisotropic nodes. If you go the the log section in Poser and start to render n superfly you will get a series of warnings where this is happening. Use that as a guide in the material room to correct that. In the material room the invalid connection lines will be dotted lines.

Energy Conservation - see this explanation in the cycles manual: https://www.blender.org/manual/de/render/cycles/materials/introduction.html