I modified the code based on your recommendation:
I used 'takeItem' and added the QStandardItem to a list with row items.
Then I take this list and use 'InsertRow' to insert it into the top grid.
I couldnt find 'insertItem' for qstandarditemmodel.. I found that 'setItem' takes way too much time, when editing a model that has already been set to the view..
It is now at about 0.86, slightly better.
I am still not sure as to why it would take as much time, when loading 100+ rows initially into the grid is almost instantaneous..
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