Two papers have provided independent attempts at comparing nucleation kinetics of seeding with the FFS dataset. Zimmerman et al. exploit that the ion attachment frequency 𝑓 + is dominated by ion desolvation and adopt the theoretical expression of the nucleation rate prefactor reported in Eq. 8). Moreover, in contrast with other seeding studies, the authors adopt the Girshick-Chiu correction As shown in Figure , these two approaches yield substantial discrepancies in the estimate of the nucleation rates, which can only partly be attributed to subtle differences in the expressions adopted for the nucleation rate prefactor. The discrepancy appears to originate, instead, from the classification criteria used to estimate the number of crystalline particles in the evolving seeds. The classification problem is discussed at length by both Zimmerman et al. and Lamas et al. . In particular, Zimmerman et al. show that nucleation rates are extremely sensitive to the number of crystal-like neighbours necessary to consider an ion part of the crystal nucleus. For example, Figure demonstrates how the predicted rates change by around 10 -15 orders of magnitude when crystalline ions are identified as those with a coordination number ≥ 4 or ≥ 6. Lamas et al., instead, resort to developing a systematic approach for the classification of the ions as part of a crystalline particle based on the analysis of the overlap of distributions of the local 𝑞 4 order parameter for a bulk crystalline phase and a bulk solution. The identification of the optimal threshold yields nucleus size estimates resorting to nucleation rates in good agreement with FFS results.