I’ve always heard NES either way, but more often it’s “N.E.S.” and SNES is “sness” more often than “S.N.E.S.” As a curiosity, I’ve heard a few folks who say “N.E.S” but also say “sness” alter the way they say one to match the other, usually by saying “ness and sness.” As I think of it, I’ve even heard “super N.E.S.”…