I've used a FL Sawtooth quite a bit and find it practical as a mid layer while wearing a pack. The insulation is over the chest and shoulders, but not on the back where your pack insulates. (I wear the crap out of this layer during the uphill portion of backcountry skiing).
Out of practical consideration of not having to mess with a blaze orange vest, I started using the Kuiu Peloton 240 in blaze orange during rifle season. I get so annoyed with taking a bino harness and a blaze vest on and off for the near constant layer swaps during rifle seasons that anything I can do to eliminate any step of that process makes the experience more enjoyable. The only downside to this layer is that it does not have pit zips for some reason. I may have some added though.
I used a Kuiu Guide jacket for quite a few years, but its since been relegated to being a truck jacket. Its comfortable, but doesn't do any one thing particularly well.