Denon: a new DCM-280 vs. a used DCD-1520

I have a Denon DRA-1035R and am looking to add a Denon CD player. I'm considering a new DCM-280 or a used DCD-1520. Is there a big sonic difference between the two?
The DCM 280 is a 5 disk CDP and the 1520 is a single disk player. Yes? I've owned the model before the 1520, the 1500mk2. Nice player. Very quick transport. Sonically, decent. Adding a DAC would be highly recommended. I believe the 1520, because of its better transport and higher quality construction would make a sonically better player. However, you might prefer the convenience of a 5 disk player. (I would consider an Adcom GCD 700 5 disk player.) Or, get the 1520 and add an Adcom/Theta DAC and I think you will be pleased.)