Carhartt makes a great waterproof jacket- I live in the Pacific Northwest, so I have had plenty of opportunity to test it. I ride in it, and it's great, because it's designed for people who move, and has plenty of logically placed pockets. It's also super durable, and the weave of the fabric makes it resistant to damage.
When it gets cold, I layer underneath it (UnderArmour, polar fleece- stay away from cotton), and have stayed warm on my visits to MT when the temp. hit -30F with a -65F wind chill.
I have two very expensive GoreTex jackets from North Face and Arcteryx, and even though I've followed the care instructions diligently, neither of them is as waterproof or as comfortable as the Carhartt jacket that I bought at the co-op for $125.00
I'd stay away from down, it's bulky and comes out if you snag your working clothes. Go to a hunting supply store or similar and buy some good, solid stuff made from light-weight modern materials (insulate, polarfleece, gore-tex, etc.).
Disagree...goose down, pound for pound is the warmest and most lightweight insulator that you can find. There's a reason that people who climb Everest and other Himilayan peaks wear goose down. They can't be all that bulky or climbers would have a pretty difficult time getting to the top.
The shell that you choose for your goose down garment is important. Forget nylon. Poplin or some other close weave outerwear fabric ensures that no down escapes the "pockets." Additionally, closely examine the stitching and the more "pockets" in the garment, the less feathers will escape with a tear. The garment should also have a consumer tag on it that indicates the amount of feathers used in its manufacture. The higher the number, the greater the insulating properties of the garment.
Goose down insulates more effectively than duck down, but is more expensive. Goose down garments are generally not waterproof, so I toss on a GoreTex jacket over the a goose down vest in very cold weather.
I have goose down vests and coats that are at least 20 years old. Yes, there are less feathers than when they were new, but they ae still the the warmest cold weather clothing I own.