Marantz CD5003 or PS Audio Digital Link III

I'm thinking about getting a new CDP since my Yamaha is 15 years old. I've been using it as a transport for 13 years with a Audio Alchemy DDE V1.1 dac. The Yamaha is built like a tank and is dead quite. My question is should I splurge for a Digital Link III or should I just go with the stand alone Marantz? By the way, the Yamaha only has optical output. Any thoughts would be appreciated.