The temptation with down jackets will get the hottest you can. If you spend the winter in northern Wisconsin as I did while trying them, that's not a bad idea. But if you are just looking for a little too hot -warming during the trips during the shoulder, or even high altitude of tag -heat backpacking, you don't need an 800 fill in power, Huge overstuffed parka in winter.
We suggest sticking to jackets that have a down rating of the fill fill of at least 500 for lightweight use, but no reason to spend on a jacket with 900 fill the power unless you go out below the freezing Temps (or you are a Continuously cold people). If you mainly spend your time in less intense climates, get a lighter jacket.
Also note that, in the case of backpacking you want to remember how to packed a jacket and how much weight it added to your pack. Unfortunately, lightweight jackets tend to be a higher fill power, as you can get more heat with less, but again, be realistic about the temperatures you are going and can You stay away from a cheaper jacket.
