Read part one.
My friend Mattia told me about this mask project and after try it I decided to tell you about my experience.
I really like the project, especially the filter fixing mechanism, it is very robust and does not require you to touch the inside of the mask. The opening is very wide and the filter allows a good air flow. From this point of view it seems to me the best. Completed the print, the mask is very clean and does not require cleaning or further activities.
However, there are two (really) minor problem: it is the slowest to print and (at least on my face) it does not have an excellent seal. The first one is not a problem, the second one is easily solved with a little rubber positioned as a gasket.