captsib -
There has been much discussion here about the"four season" descriptor that Keystone uses to describe and advertise their RV's. Often, there is a sticker by the entrance door that reads "Polar Package", "Arctic Package" , or some other similar label.
Keystone likes to tout the "heated underbelly and tanks" as two of the features that makes it 4 season or able to survive sub freezing temperatures for prolonged periods. On its own, I do not believe for one second that any of their RV's are capable of doing this without some kind of skirting or additional heat source. The heated underbelly for example, will only receive "heat" when the furnace is running. And any heat that it does receive is quickly lost in the underbelly and all its openings and poor insulation.
It also depends upon where you live if you think of it being "4 season". If you do not see many days of cold weather or rarely have freezing temperatures, then this description might hold up. Otherwise, I would not make a claim that it is 4 season. Ask anyone who spends their winters in the NE, or north central states of the US or the Canadian Prairie provinces. I doubt if you would find any folks out camping in December in those places!
Three Season -- sure. Four Season - Maybe .....depends where you live.
Welcome to the forum BTW