I just bought an insulated parka after using the fleece and shell type layering for the last 12 years. I still go for a sweater under a light jacket most of the time, but when it gets really cold the parka is so convenient. I love not having to worry too much if my sweater is quite warm enough, or having to fight with 3 layers taking them on or off when I go out. If you can offord to own more than jacket, I think its totally worth having.