borninblue, we have always used our RV's for ice fishing and as our snowmobile cabin. Non side units are much warmer and we don't have to climb up onto the slide roof to clear off ice/snow in order to close it. In our experience propane use is greatly reduced with a non slide unit. (most slideouts have less insulation than the rest of the RV)
During the real cold (-25F) riding season, we use it to dry camp , using the heated CG bath house and a CURVE porta potty inside our TT during the night.
We keep (store) my machines where we ride, so we don't have to transport the sleds and an RV. When we return home, we use our oscillating lawn sprinkler hooked up a hot water line to wash off the road salt on the underbelly.
Someone made a good point regarding the enclosed dump valves, I wish I had that set up. I don't know which Jayco models have that.
I think the Jayco you are interested in uses the exposed valves but im not 100% sure.
One nice thing you do have is a floorplan that allows you to have a heat duct in your bathroom . My Jayco 23RB does not have a heat duct, the door has to be cracked open or use an elec. heater on low. We always have elec. to use, so its not an issue for us.