Thanks for the comments and email, Audiovoice. It sounds like the TDS enhances the Planet well.
Aside from the Margules unit (I had 2, sold one, and will put the other in my second system soon), I use the Taddeo Digitsl Antidote II. I have the Active version, incredible unit, best of any post-digital analog processing for me. They aslo make an inexpensive passive version, similar effects, but perhaps rolls off the highs more. Still a nice upgrade to many DVD's, Laserdiscs, or older CD's otu there.