I'm curious if anyone has ever tried stacking UQs and how much success they've had with it. I have a 45*F summer UQ and a 20*F spring/fall quilt. I would like to get into winter camping but dont want to invest several hundred more in 0*F quilts just to find out that I don't really like it. So what I'm hoping to do is first put on my 45*F quilt and then my 20*F quilt on top of that.

I think I read before that when it comes to over stuffing 1oz down is equal to an extra 5*F of warmth. Since my SS UQ does not list the amount of down used (overall weight is 10oz though) I will just say lets pretend it's 8oz of down, which would be 40*F worth of extra warmth. However that would imply that the two could take me down to -20*F, which seems like far too much.