Music of the Spheres founder, Larry Roark, designed his chimes in a variety of musical scales so you could choose the one that sings most sweetly to you. The eleven musical scales they make are divisible into two main categories of music which we can simply call the "more familiar" and the "more exotic" sound.
Pentatonic Quartal Chinese Mongolian Westminster
Hawaiian Japanese Balinese Whole Tone Aquarian Gypsy
You will find the distinctions between the categories easier to make than the distinctions between windchimes within a category. The "familiar" major scales are quite similar one to the other, while the exotic scales are only somewhat similar one to the other. If you are having trouble deciding what you like, first determine the category that pleases you and focus there. Listen and watch for a tuning that seems to make the lines in your forehead relax more quickly, or one that begins to bring a sense of ease or calm. Let your mind relax and enjoy the process, it's not an intellectual exercise. And besides, there's no wrong answer.