Generally they are outstanding, some are terrific. Depends on the quality of the Playback System. I am not up to date now but I think there are cheap XRCD's (avoid those) and the more expensive ones, these are the ones to buy (see Pic)
I'm really surprised - even our gifted Denon midi shows a clear distinction between standard and XRCD. I'd expect your CDC to do the same - the difference is in the quality of the recording, something most replay systems should have no trouble with demonstrating.