Subwoofer connection XLR vs RCA

My pre-amp is the NAD C658, which has XLR outs to the amp (which I am using), then two RCA jacks to connect to two subwoofers.  I’m obtaining a B&W DB4S subwoofer which allows for either XLR or RCA connections. My preamp to subwoofer distance is short. 
the easy connection is to simply use the RCA Jack setup which I’m currently using with a Klipsch subwoofer. 
my question is would there be a benefit to connecting with the XLR over the RCA?  If so, then the challenge would be how to do that…I’m hesitant to use a splitter off my preamp outs, I don’t want to degrade that primary signal plus that would be feeding a full range frequency to the subwoofer (probably not an issue…?). 
thoughts?