I have two bags. One is my "beater bag." It is a Kelty Lightyear 25F (more like a 35 or 40 F) that I use for summer. I don't worry to much about it getting dirty and whatnot. My other is a WM Ultralight Super with overfill. That's my shoulder season bag. If I ever get into serious winter trips then I will pick up a zero degree bag. I doubt I would ever need one around here in Western PA.