Does balanced interconnect sound beter than RCA?

I'm in the process of upgrading my system and looking at new/used integraged amps. The amps i am considering are the sim i-5, the plinius 8200 mk 2, perreaux 200ip and the classe cap151. Some have have both balanced and RCA connectors for the CD player and some don't. Can you hear the difference of the Balanced connection versus the RCA connection? It seems that their is a lot of very expensive equipment that does not have balanced connections which would seem to indicate that it doesn't necessarily need to be there. Is it worth getting an amp or cd player that can utilize balanced connections?
thanks,
jmillen