One could have a religious argument over two boxes versus one and get nowhere. There are trade-offs involved in each design but there are other more significant sources of the differences in sound you encounter with CD players. I reckon you should rule out neither and audition anything in your price range - whether one box or two. If you are really spoilt for choice, Garfish is right to imply the one box player makes things simpler - a good thing.
CD player or Transport and DAC
Wanting good sound but not wanting to throw money away, how much more do I get for a separates source than for a single unit? As an example, scanning the for sales here, a Wadia 860 weighs in at $4,500 and a 27ix / 270 combination at $10,000. Similarly for ML equipment. So how much more do I get for the extra $5,500? Any thoughts and experience and other ways of achieving similar quality?