QTableWidget::setCellWidget() a QLineEdit for very large table?

Hi, I have a QTableWidget in my Main Window. Now I know that we can set item as QTableWidgetItem for each cell. Instead I wanted to ask what is the effect of adding QLineEdit through setCellWidget() for each cell, rather than QTableWidgetItem through setItem(). I want to know whether there is any impact on speed on my application? The tablewidget has >10,000 rows & >10,000 columns. So which one of the 2 mentioned above is better to use for faster & less dynamic memory consuming application? If I could not make my question clear enough then please feel free to ask for details. Thank You.