If you do not have the Plotter software, it is well worth having. If you get into testing, you can pick up an X-Rite densitometer easily for <$100 and do as many film and paper tests as you want. Especially if you are using relatively expensive materials such as TMAX, Lodima, and Amidol you will probably save money in the end.
Thanks Jerold. The Plotter Software may be a requirement sooner rather than later.