I think your description of Rhodium is spot on plus it often takes 500 hours to fully break in. I have compared the GTX-D Rhodium (nonNCF) to the Synergistic Research Blue outlet and I really like The Blue outlet. The sound is more precise without being hard or bright. The music has a relaxed flow but with wonderful details and a full bodied texture to individual notes.
I also like the fact that the Blue outlet comes with a 30 return and during September there is a special that gives you a free Synergistic Research Blue fuse with the purchase of a Blue outlet.
I hope this is of some help.
David Pritchard