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I tend to look at these things through my English prism, which often has Germanic/Latinate pairings, the former being the "earthier" word and the latter the more "sophisticated" (car/automobile, dog/canine, sun/solar, etc.). So, too, in Japanese where the Japanese Japanese "休みの日" is "earthier" and the Sino-import "休日" is slightly higher-brow. Not a matter of correctness, but sometimes one of register. As a non-native, I don't feel a big diff here, but the Sinoversion is shorter, obviously, so it might show up more often on spatially challenged signs :)
