Environmental Sealings For a camera that you carry everywhere with you, being weather proofed is a big advantage. You will have one less thing to worry about.
Large Four Thirds (17.4 x 13 mm) sensor Large sensor in Olympus E-M1 II ensures a good low light image quality compared to smaller sensor, and it also provide shallow depth of field and a nice blurry background when needed.
Medium size Body With relatively smaller body compared to DSLRs and better ergonomics compared to Compacts,Olympus E-M1 IIis a good compromise between size and functionality.
574g Carrying this weight all day may not be very comfortable for you.
Body Thickness 67mm With a thickness of 67mm,Olympus E-M1 II is not a pocketable camera for sure.