It never being too early to start preparing for white season I thought I'd mention something again and early.
Lately I have seen a lot of the older style ThermaRest small mats for sale and at bargain basement prices [ I paid $5- each at the Salvos last year] and with comfort mats getting thicker and thicker we are winding up with less room inside our tents.
My experience has been that in white season putting the insulation under the tent floor works better; so to that end if you are thinking about a winter trip perhaps you should be looking for cheap SI mats in the original 25mm thickness.
Three of the small mats laid across the tent will cover most bushwalking winter tents.
Naturally any insulation under the floor works, CCF works as well but is more bulky and also naturally thicker is better.