I purchased 2 lenses recently... a 50/1.8d for my d700, and an Oly 25/1.8 for my ep5. Due to the small u4/3 sensor, both offer identical fields of view. Over the next few weeks, I'll shoot fx and u4/3 side by side, allowing me to compare the results from my tiny mirrorless rig and my big rig. Afterwards I'll decide if there's merit, for my purposes, in maintaining 2 expensive systems. I'll post my observations here.