1 and 2 have been well covered by others. As to 3, I usually leave my car set to auto for the climate control, with the ac turned off. set like this it will blend heat as required to keep the temp where you want it in the cabin. I do not have the cooled seats in my 14, just heated, and usually drop the temp setting to 1 after I start to feel heat, as on 2 or 3 they're too hot for me. I believe my wife sets them at 2. Her Excursion only has single stage heated seats, and she uses them, but I find them too hot to use (I'll turn them on, and as soon as I start to feel them I turn them back off, just to take the chill out).