Camping in the dead of winter (below 0 degrees extended time) sounds like an adventure but it's not. I did it for three winters in a TT that has the "Extreme Package". If you do, get the best thermal coveralls and electric socks you can afford. Be prepared for frozen holding tanks and elbows, water backed up in the shower, iced windows on the inside, etc. I'm sure you get the picture. Four season TT is marketing hipe and only good to about 20 degrees. I never owned a fiver but it would probably do better.