SelectedItem C# WPF вместо SelectionChanged

Что лучше использовать? Вместо SelectionChanged использовать SelectedItem

private Game _SelectedItem;
public Game SelectedItem
{
    get { return _SelectedItem; }
    set { _SelectedItem = value; OnPropertyChanged(); System.Windows.MessageBox.Show(((Game)value).Creator); }
}

или все таки так

<ListBox ItemsSource="{Binding Games}" Background="#FF292D32" HorizontalContentAlignment="Stretch">
    <i:Interaction.Triggers>
        <i:EventTrigger EventName="SelectionChanged">
            <i:InvokeCommandAction
                Command="{Binding ItemChanged}"
                CommandParameter="{Binding Path=SelectedItem, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type ListBox}}}" />
        </i:EventTrigger>
    </i:Interaction.Triggers>