If you don't need the robust weather sealing, the EM10ii has most of the features of the EM5ii and similar IQ. I use it often with FD 50/1.4 and FD 50/1.2 and sometimes an FD 135/2.8 without any issues. I also have a Nikon to MFT focal reducer that allows me to shoot Nikon AI lenses a stop faster.