As for my own experience, sound quality is always improved by the replacement of RCA cable with XLR cable.
Should I upgrade to XLR interconnects?
I recently purchased a Marantz SA-11S3 SACD player to pair with my Marantz PM-11S3 integrated amp. The SA-11S3 has balanced outs and the PM-11S3 has balanced ins. Currently I am using RCA interconnects. Is there any benefit to upgrading to balanced for these particular units? I do not want to drop big bucks on new cables if the benefits are minimal.