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         Avoid setting cell style properties for individual DataGridViewCell or DataGridViewRow objects. This includes the row object specified by the RowTemplate property. Each new row that is cloned from the row template will receive its own copy of the template's cell style object. For maximum scalability, set cell style properties at the DataGridView level. For example, set the DefaultCellStyle property rather than the DataGridViewCell.Style property.

         If some cells require formatting other than default formatting, use the same DataGridViewCellStyle instance across groups of cells, rows, or columns. Avoid directly setting properties of type DataGridViewCellStyle on individual cells, rows, and columns. For an example of cell style sharing, see How to: Set Default Cell Styles for the Windows Forms DataGridView Control. You can also avoid a performance penalty when setting cell styles individually by handling the CellFormatting event handler. For an example, see How to: Customize Data Formatting in the Windows Forms DataGridView Control.

         When determining a cell's style, use the DataGridViewCell.InheritedStyle property rather than the DataGridViewCell.Style property. Accessing the Style property creates a new instance of the DataGridViewCellStyle class if the property has not already been used. Additionally, this object might not contain the complete style information for the cell if some styles are inherited from the row, column, or control. For more information about cell style inheritance, see Cell Styles in the Windows Forms DataGridView Control.