The thick woods and brush busting for grouse in hilly terrain, I don't like the length of those flatlander guns they use in the open fields. All my upland guns used for grouse, all had shorter barrels.
The reduced length is a charm in the woods, on that nano second snap shot on a flushing grouse, with only a 2 ft window between spruce thickets.
This one here with about 40” in overall length and a sleek 6 lbs is perfect!:
https://cz-usa.com/product/cz-redhead-premier-reduced-length-20-gauge-24-barrels-13-lop/