Sony CDP 559 ES or Marantz CD63 KI?

At the moment I own a Marantz CD63 KI cd player, which has a warm, smooth sound. Someone offered me a Sony CDP 559 ES player for around 240 bucks. It looks good, but I am not able to hear it in my own system untill I buy it. Is it worth the money? And would it be an improvement over the Marantz?
My systems comprises of an X-Pre/X-Psu preamp, class A (the real stuff) poweramp and a pair of self built speakers.
Any input appreciated...
I don't think it is worth it except for reliability. One of the biggest steels would be to find an older but way ahead of it's time and grossly under rated Kinergetics KCD-40. This 12 year old design sold for $2200 and was way under rated and held it's own against Wadia and Theta. Because they are out of buisness you could find one used for around $300 - 400 and it would make the Sony sound like a Fisher Price or Yamaha.