cd player/transport to external DAC 500

I am looking to purchase a CD player or transport for a 2.1 audio system, preferably under 500, but I will stretch a little if I need to. I am planning to connect this player to an external DAC, probably via digital coaxial, though I'm open to other possibilities. Since this connection will be made digitally, does the DAC of the actual CD player even matter? I was planning to buy a Cambridge Audio 640C v2 for 349, which seems like a great deal, but in thinking about this, it seems that I am "wasting" the DACs in the 640C. Is there a player that would act as a better transport than the 640C at a similar price point, perhaps with inferior DACs? Ideally, I would like it to play at least CD-R and more audio formats would be a plus, but not necessary. Thanks very much for your advice.

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