Walt, you have a Big Sky, maybe your insulating factors are different that Montana, and different again from Mountaineer?? I have not kept those numbers in my ole leaky brain, but, you are supposed to get something better for your Big $ky $$$$$.
I always thought that artic package stuff was mostly for the basement, to keep our water running. But, then, there is that leaky brain stuff again. SIGHHHH
And, then factor in personal differences. Yesterday I was photo recording some headstones, it was 40 and breezy, I had on the thermies, jeans, warm socks, t shirt, sweat shirt, good jacket and ear muffs. My fingers were icy. There was a guy in the cemetery at the same time, talking to Al, (who was bundled up even more than I was) who was in a cotton short sleeved shirt and jeans and was NOT cold. I am always cold, guess this guy isn't.
Something else we notice, if it is calm (as in no wind), colder temps outside don't bother us too much, but add in a breeze to a wind, and there is a HUGE difference in our unit (read year and stuff below in the sig line, we don't have as much artic package, etc as MOCers with newer units). Yepper, when that wind blows, you will find us adding another layer of clothes or just crawling into bed with a good book, 3 yorkies and several blankets. Hoodies, optional.