Rick that is a good question.
My audition lead me to several Pre Amps including Shindo, Aesthetix's, C2300 and McIntosh C46 which I ended up buying. But I could have easily bought the Aesthetix's and tweaked with upgraded tubes and fuses. Within a year, I ended up buying the C500 after listening to C1000.
My observation is I don't know if the C2300 is going to be significantly better than Aesthetix's combo. I do suggest investing in higher quality tubes for Calypso and Rhea as I did for the C500.
Keep the Asetheti'x combo unless your going to move up to C500 or Callisto Eclipse.