DirectCast vs. CType

Public Class Form1
    Private Sub ButtonCTypeR_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ButtonCTypeR.Click
        Debug.WriteLine("CType on a reference type")
        Dim StartTime As Date = Date.Now
        For i As Integer = 0 To 1000000
            Dim MyObject As Object = "Hello World"
            Dim MyString As String = CType(MyObject, String)
        Next
        Debug.WriteLine(Date.Now.Subtract(StartTime).TotalMilliseconds)
    End Sub

    Private Sub ButtonDirectCastR_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ButtonDirectCastR.Click
        Debug.WriteLine("DirectCast on a reference type")
        Dim StartTime As Date = Date.Now
        For i As Integer = 0 To 1000000
            Dim MyObject As Object = "Hello World"
            Dim MyString As String = DirectCast(MyObject, String)
        Next
        Debug.WriteLine(Date.Now.Subtract(StartTime).TotalMilliseconds)
    End Sub

    Private Sub ButtonCTypeV_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ButtonCTypeV.Click
        Debug.WriteLine("CType on a value type")
        Dim StartTime As Date = Date.Now
        For i As Integer = 0 To 1000000
            Dim MyObject As Object = 123
            Dim MyInt As Integer = CType(MyObject, Integer)
        Next
        Debug.WriteLine(Date.Now.Subtract(StartTime).TotalMilliseconds)
    End Sub

    Private Sub ButtonDirectCastV_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ButtonDirectCastV.Click
        Debug.WriteLine("DirectCast on a value type")
        Dim StartTime As Date = Date.Now
        For i As Integer = 0 To 1000000
            Dim MyObject As Object = 123
            Dim MyInt As Integer = DirectCast(MyObject, Integer)
        Next
        Debug.WriteLine(Date.Now.Subtract(StartTime).TotalMilliseconds)
    End Sub
End Class