This seems like a really interesting work in terms of synthesizing and systematizing the known reactions/fluxes in a minimal cell. However, the paper seems to be like many other modeling studies in the field of microbiology - there are either no, or very few testable predictions made. It's hard to think of the model of metabolism this paper presents as valid without at least some idea of it's predictive accuracy. The concordance with previously published results does not seem like very strong evidence.