I used hogs fuel the first year I lived on my farm. By spring it was broken down and I didn’t want to get a new layer every year so I went with gravel. It was more expensive than the hogs fuel but is cheaper over time since it doesn’t need to be redone every year. I graveled my mare’s paddock 9 years ago and haven’t needed to redo it.
I’ve found it’s best to lay the gravel in August or September when the ground is dry. A friend waited until later in the fall and her gravel sank down and mixed with the mud.
I live in the PNW in an area with a 3-4 foot layer of clay for topsoil, without something added the traffic areas turn into at least knee-deep mud. Hogs fuel works into the mud throughout the season. The gravel, if you get the right type and put it in when the ground is dry, will form a layer on top of the soil.
The barn I where I boarded my horse before I bought the farm, maybe 10-12 miles away as the crow flies, had a different type of soil. More rocky instead of clay. They could use hogs fuel in their paddocks but needed to bring in a new load every year or so. I wonder if PNWJumper lives on a similar soil type?