By popular request, well a couple of people asked, I thought I would attempt to answer a question that I quite often see discussed online that is “How much better is the image quality from the Olympus M Zuiko 300mm f/4 Pro than the Olympus M Zuiko 4-150mm f/2.8 Pro with the MC20 2x teleconverter ?”
Olympus 40-150 + MC20 or Olympus 300
A Good Place to Stand 