I currently own a NAD C320BEE integrated amp and a NAD 521i cd player. I have them hooked up to a pair of Wharfedale Pacific Evo 8s. The system is wonderful, but I have heard that I could improve the sound by upgrading my cd player. I was looking at either the 521BEE (the new version of my 521i) or the 541i. Is the upgrade worth it? I listen mostly to jazz and classical music.