I made this video about the reasons why I personally switched from a Sigma 35mm Art to the Canon Rf 35mm f.18. My points are designed mainly from a view point of a photographer and part time use for video. As a hybrid shooter, the canon RF 35mm makes a lot of sense for the Canon mirrorless R system. Besides an opportunity to save some money and getting the native RF mount benefits, it is smaller and has quiet auto focus and good minimal distance focusing abilities.
Canon RF