The weather's finally getting colder, and I'm getting amped up to do a lot more winter camping this year. I camped out a couple of times last year in ~15*F weather, and found that it was pretty decent, but I want to have a better setup this year. Here's my gear:

-Teton LEEF 0*F sleeping bag
-Klymit static V insulated mat, R-value of ~4
-Alps Lynx 1-man tent (actually a 3-season tent)
-old Sigg stove that needs to be replaced

I'm pretty well set on warm clothing and boots; I'm just looking for some gear advice. I sleep with my dog in my sleeping bag with me, which helps with warmth overnight, but I should definitely get a larger sleeping mat, new stove, and a 4-season tent.

Recommendations would be very welcome.

I'm thinking of related for a tent - Alps Tasmanian 2.