VBA Arrays - Faster alternative than Vlookup?

Worksheet function calculates faster in the range.
If you explain more about what you are really trying to do, there may be a faster way.
e.g

Sub test()
    Dim a, x, s As Double, msg As String
    With Range("a1:a65535").Resize(, 2)
        .Formula = "=row()&char(column()+64)"
        s = Timer
        x = WorksheetFunction.VLookup("50000A", .Cells, 2, 0)
        msg = "Range:" & vbTab & Format$(Timer - s, "0.0000")
        s = Timer
        a = .Value
        x = WorksheetFunction.VLookup("50000A", a, 2, 0)
        MsgBox msg & vbLf & "Array:" & vbTab & Format$(Timer - s, "0.0000")
    End With
End Sub