Yep, I seem to be in the minority, preferring the Rubinstein stereo to the 1950's mono set. It may just be a matter of greater familiarity -- I will definitely give the mono set a serious re-listen soon.
Agree that the autumnal thing can be overdone -- you hear it all the time, for instance about Bruno Walter's Columbia Symphony recordings. But it's a useful verbal crutch for me when trying to describe how I hear these: there's a certain aristocratic quality about them, a slight reticence and holding back in the dancing melody that enhances rather than diminishes the experience; as I said, it's a purely gut-level reaction, so it's hard to describe...