User Review: Rab Men's Generator Jacket
Fill: Prima Loft
Price Paid: $105
This is a really good piece of gear. It weighs less than 10 ounces and it offers quite a boost to your insulation.
When backpacking, I use down insulated sleep gear. I've always been concerned about my gear getting wet, but I do not like the weight penalty of synthetics. Now for less than 10 ounces, I have an insurance policy against wet down.
Normally I stay warm into single digits with just a windshirt and a long-sleeved base layer when carrying a backpack as long as I am moving. For times that I am still or in camp, this pullover does a great job of keeping me warm. I find it also gives my sleep system an extra 25 F when combined with a warm hat for those times when the temps dip lower than forecast. If not needed for extra insulation, it also makes a great pillow when stuffed into its internal pocket.
The Pertex shell is light weight, so you might want to wear it under a shell if you'll encounter branches or rocks. The DWR will shed a light drizzle, but I would not wear it as an outside layer in heavy rain.