The only due diligence you really need to do now is to audition the Simaudio player, though if what you heard with the Playback Designs really blew you away, I'd say go for it. Sometimes you hear a component that you know is "right"--that's happened to me a couple of times, and I have not regretted making the purchases when that happened.
Playback Designs MPD3 or Simaudio 650d
Come on guys chime in on this one. I've my homehad the pleasure of the mpd3 in my home for a three day audition and have been blown away. I have not heard the 650d bu t its on my radar even though its 1500 more. So before I pull the trigger I'd like to complete my due diligence and look to all of you for some welcomed feedback.