We recently sold our 40' Keystone Fuzion to upgrade to a MH. Ours had bunks in the garage plus a loft. Being that we have 4 kids it worked VERY well so they each had their own bed. We traveled in all sorts of weather conditions and never had a problem with them being cold. The Fuzion has a glass patio door dividing the living area from the garage giving the feeling of much more living area. If we knew it was going to be cold we would use and electric heater in the garage as a back up. Maybe all toyhaulers have it but ours had washer and dryer hook up. We didn't use it but it was available if we wanted. One thing to note is the Fuzion we had did not have a heated underbelly which could be a problem if dealing with long term cold.
Kids are growing up and leaving home... time for us to move on. Lovin' the new MH