I just got a new jacket that I'd ordered. I wanted a shell with large pockets that would hold my new camera. I couldn't really tell from the photo or specs if it was hard shell or soft shell. Turned out to be soft shell. Nice jacket for $20. Man, I love Sierra Trading Post.
I have a ridiculous number of jackets, both hard shell and soft shell. Soft shell is nice. It's supple, stretchy, and quiet. But it does have a couple drawbacks. It's generally heavier than hard shell and takes up more room in my pack. Soft shell isn't just one material. I have really thin soft shell jackets and some pretty thick soft shell jackets. I have a Gore Running wear Windstopper jacket that I just love. It is made out of a really thin, light soft shell fabric. I have other jackets that are a really thick, heavy soft shell material and wear them mostly around town.
My question is, do the thick soft shell jackets offer any significant insulation value? None of them seem to make that claim. I've heard them referred to as warm, but everyone seems reluctant to claim any insulation value. If they have none, I find it hard to justify their extra weight and bulk. My personal experience is that they do add some warmth, whether you call in insulation or not. On the other hand, a heavy soft shell can compress the insulation of a puffy jacket. I'm inclined to only wear them over fleece or alone.
I guess my favorite shell material is a soft shell of the thin, light, stretchy variety. Hard to find, but grab it if you do.