Hi Jamie,
apart from the methods you mention, if someone just wants to get a custom entry into the log file to monitor a variable etc then there is a very simple method available from the script task:
Dim dataBytes(0) As Byte
Dts.Log("My custom message here", 0, dataBytes)
or from the script transformation:
Dim dataBytes(0) As Byte
Me.Log("My custom message here", 0, dataBytes)
Rgds,
Paul Ibison