I use the 40mm and 28mm Voigtlander pancakes on my BMCC and have been pretty happy with the look it gives. A little green color shift but not bad. I have the 20mm also and its almost un usable. The 40mm is the best though. When using with Tiffen screw on ND's they definitely keep the rig small and balanced for hand holding well. Too bad that 17mm isn't a pancake, that camera body is so small the 17mm must counterweight it in a bad way, correct? Perhaps your using it on sticks though.