Question make a tree show ready

I have a question to make a tree show ready. What is the most beautiful, the soil with moss or a layer of fine akdama.

It is a matter of personal preference, I suspect. There may be an occasional time when the species of tree matters -- trees that grow naturally in arid lands may do better with the "sandy" look.

I tend toward moss, and not necessarily a solid carpet of moss. The problem with moss -- especially when your soil is as hard-looking as yours appears to be -- is that you have to lay the moss several weeks beforehand so it looks established.

It also depends on the custom or rules of the particular show. At the high-falutin regional or national shows, you are usually expected to use moss. The local club shows have more leeway.
For those of us who live in the North and grow both tropicals & temperate trees, it is almost impossible to establish moss on most bonsai for any length of time. It certainly doesn't survive indoors over the winter, and in our dry summers, it doesn't survive outdoors in the sun in a bonsai pot. We have to apply it at the last minute. When moss is not available or practical, I use a top dressing of dark colored mame soil.
Iris