There are two different styles for the Validation Message - the Microsoft's and the Telerik's.

Scrollbar scrolls unexpectedly when column width is changed. Check the following video for a reference:
http://screencast.com/t/Y6IwtREc

WPF Controls Samples -> GridView with Data Virtualization -> Edit UnitPrice and press Enter -> press ESC -> press Control+End.

Workaround: press ESC one more time or commit the edit before pressing  Control+End.
* works fine with QueryableCollectionView.

When a SortDesciptor is applied and items are modified, the selection behaves inconsistently:

1. If an item is modified, so it's position needs to be changed according to the sorting descriptor, it will be removed from the SelectedItems.
2. If an item is modified, but it's position should remain the same, it remains in the SelectedItems collection.
2a. If IsSynchronizedWithCurrentItem item is set to true and the position should remain the same, the item is removed from the SelectedItems and the one that goes in the same position is added to the collection.

Workaround is to add the item back to the SelectedItems collection when RowEdit ends.

private void clubsGrid_RowEditEnded(object sender, GridViewRowEditEndedEventArgs e)
{
    (e.Source as RadGridView).SelectedItems.Add(e.NewData as Club);
}

ValidationErrorHandler does not get invoked when validating in view mode and System.ComponentModel.INotifyDataErrorInfo interface is implemented.

New row in Bottom position is not visible in the child grid when the grid has no items

HeaderCheckBoxStyle of GridViewSelectColumn returns TextBlock as Header in Office2013 theme