An additional thought; I have not found the sound of an economical sibling player used as transport to be identical to the more expensive model when shunted through a DAC. Though the laser assembly is identical in many cases, the difference in topology is such that the performance is significantly different (let's say, with $40K rigs as a baseline) even when the player is operating as a transport. Whether such differences are worth it to you - well, that's your call.
Questions such as:
Will the performance of the less expensive player operating as a transport exceed that of its internal DAC? (possibly, depending on external DAC and Digital cable)
Will such a CD1S with external DAC exceed performance of the CD-2? (Doubtful; you may come closer, but then you're spending nearly the cost of the CD-2)
My guess is that the CD1S with the Cambridge Audio DAC Magic might be a really fun, good performing combo. It's a combo I might try if I had the time. You might end up finding that it's not significantly better than the CD-1S alone. It's extremely difficult to cobble together economical sources which are hugely better than a primo cdp.
Absolute answers to such questions would only be found by actually doing the comparisons.
