music hall dac25.2-rca or xlr?

Just got a new music hall dac25.2 which sounds great. I had to order cables so they loaned me some rca cables that sound pretty good, but now i read that xlr cables bypass the tube and rca cables utilize the tube.
Does anyone have experience with either or both rca and xlr? What is your preference?
It seems like using the tube is the whole idea. Any Input?
Haven't tried the balanced out since I can't use them but the RCAs out with the tube sounds great. I know this doesn't answer your question but from what I'm getting out of mine, you should have no qualms just using the tube outputs.
The tube out imparts just enough warmth for my SS system.
on a side note, why can't you change what information is being displayed on the units display