Regarding how easy it is to set up, fill with data, maintain and if there is any speed differences.
IMO none of these is relevant for the decision whether to use a table or grid layout. Instead it depends on the type of data and semantics.
A typical example for a table is an address list: The header contains "first name", "last name", "ZIP", "city", etc. And there is a relationship between the headline and the values below: E. g. below "first name" there are the first names of the individual persons. And in one row all the data belongs to the same person.
On the other hand in a grid there is no such relation, all cells are independent (though in some special case there may be a relation but this is not necessary). A typical example is an image gallery.