ARCAM CD23 internal DAC vs. stand-alone DAC

Further to my post regarding the latest Benchmark DAC vs Bel Canto DAC - I'm wondering if it would be worth adding a modern $1000 stand-alone DAC to the CD23. A few years back the internal Ring-DAC was one of the best available and adding a separate DAC would not be an advantage. But now that DAC chip-sets have advanced (along with reclocking circuitry) to the point where, "the Benchmark sounds better than a $10K DAC available a few years ago...and is a giant killer", is this still the case? This question pertains to the older and original CD23, not the latest and greatest CD33.