I prefer the fanatic over the heavyweight, but this is for treestand hunting and not active hunting. I think both would be pretty heavy on an active hunt unless is was used as a solo midweight, but in my mind there are so many other better choices for that. Breathability/mousture movement being the stopping factor there.
In my treestand use, i will use the fanatic over the hvywt since it does have the little glove thingys and the kangaroo pocket. Its great in a cooling 60-65 degree evening to be able to grab a little extra warmth from those two features. I dont wear this as a standalone below 60 usually and windy days i reach for the stratus jacket for the wind barrier. But on a calm 60-65 degree day, it can go alone.
I do wear these both under a stratus jacket down into the high 40’s. They perform really well as a static “insulator” piece, and the hood on the fanatic is useful here but much below 50 and i am reaching for a jetstream beanie
In my opinion, pick one you like for its features and go with it. They are very similar weight material, but the features make each fit uniquely into different niches