Here is another Hauser style build. Fitting the sides to the top and neck.
I find they add more clarity to the notes, but I actually prefer what Hauser ii and iii have done and that is to get rid of them and the notes blend a little better. Hard to describe it, but I have the sound in my head. IMO the Oribe bracing is achieving something different. I have tried that bracing and find that it makes the vibrating surface smaller which is a good thing. Impedance matching. Nylon string guitars have the right volume of air but too big a vibrating surface. By making the vibrating surface smaller you match the string output. Dammann makes the inner vibrating surface smaller for impedance matching as well but he uses large tentellones