Considering switching to XLR cables,

That sounds a little presumptuous. Perhaps you mean when you have compared single ended to XLR on your equipment, you have not heard a difference. If so, what was the equipment in you were using and which interconnects did you try? Were the components balanced... etc. 

If your equipment is fully balanced, then absolutely use XLR cabling. Why would you downgrade what the designer put so much money and effort into......obviously they feel it's the best option. If not, then try and see which one you prefer. If the cable run has any distance and accepts XLR, that might be the best choice

I went through a period with my system during which I sometimes mixed XLR and RCA IC's between components to get different effects but ultimately found that using RCA throughout was best. Mixing them created "collisions" in sound - the XLR gain was too dynamic for the mix and would actually cause audible "skips" in the playback. Eventually I used all RCA's (Moon Audio "Silver Dragon" RCA's) and this created the sound I was looking for. When all XLR's were used the sound was too dynamic and "slammy." The power amps are  GanFet AGD Audions which are already "fast" amps, so XLR's were sort of overkill. The Dac and pre were Holo Audio, and there has always been a rumor that the Holo May prefers RCA to begin with. I would have to agree. Also, when using the Primaluna EVO 400 as the preamp the RCA's are definitely superior.

These components are all pushing a pair of Cornwall 4's with vintage 10 gauge Western Electric wire used as speaker wire. The power cables are a mix of pre-owned Shunyata Alpha NR's at the CD transport and Holo May Dac and Anticables Level 3 everywhere else - the trials and engaging mysteries of a relative newbie in audio electronics.