I am basically that guy who is out running before the sun comes up, anytime during the year in SE Nebraska. Temps range from -30 F to +95 F with as much humidity as the Gulf Coast. Picked up the Rab Paradox after reading a blub or two. I have an Eddie Bauer Propellant jacket w/ Polartec Alpha and use it in the snow for hiking, snowshoeing. It is heavy, at 702 grams but dumps heat and moisture like nothing else.
I put on the Rab this morning and hit the trail; dark and chilly at 48F around 5am. Soon after starting, I hit that point when I should be warming up and getting a little sweat buildup but was comfortable, cool and dry. Ran for a little over 5 miles and made it back to the car, still cool and dry... just the perfect finish. I wore the Paradox over a lightweight short sleeved 85% polyester, 15 % cotton tee. This will be a great mid layer under a wind jacket for running and fast packing this winter. At 320 grams for a large size, it will definitely find room in my backpack.