I'll start by saying that I am very lucky to be able to have the heating on 17 whenever I'm at home, which I realise is fortunate compared to some people who can't afford to have it on at all. But I have always really felt the cold, and always had the heating on 22 during the day and 18 at night (at night, I know!)
This year it's been left on 17 and I'm not really cold at all. I think I used to just whack it up high on the first cold day and then got used to being toasty. I'd never go back to having such a stuffy house now. I do know I'd feel differently if my house was much colder though.
How have others been finding it?