While I don't have my 990 YET.......I felt the need to put my 2 cents in here.
I've been an AV hobbiest since 195X....

I also worked in the technical end of Hollywierd for some time.
I've never been able to hear a difference between the two types of cables.
My one main objection to the XLR connectors is the distance they protrude from the unit.
I have some Mac Intosh equipment that has them and I've never taken advantage of them on a permanent basis.