Hello, I remember the first time I rode on a wooden floor at a contest and it was horrible. But not because of the surface but because it was flexing a lot. I think it became an option for contest because you can build it up and remove it after the contest. You can also protect a sensitive indoor floor for example. If you think about building a spot I guess it will be cheaper. It also leads to less wear of your tires.
My personal opinion is that I prefer a fine asphalt or concrete.