I use only JPG. I have not tried with RAW and I am not in to post processing (yet!). See below for sample images with neutral setting and with highest sharpness. I also included 100% crop that showcase the difference.
Neutral
Highest Sharpness setting
Neutral 100% Crop
Highest Sharp 100% crop
Unfortunately, you will have to download the file to view the EXIF information. For me these picture will show that the photos are very soft at neutral. Also the color tone of image with highest sharpness seems to be different that of neutral though all the settings were the same.
I shall try to see from RAW if there is any noticeable difference and will upload more pics. Below are the original resolution pics
Thanks for all your suggestions. I really want to find out why.