  Path sampling approaches have become invaluable tools to explore the
mechanisms and dynamics of so-called rare events that are characterized by
transitions between metastable states separated by sizeable free energy
barriers. Their practical application, in particular to ever more complex
molecular systems, is, however, not entirely trivial. Focusing on replica
exchange transition interface sampling (RETIS) and forward flux sampling (FFS),
we discuss a range of analysis tools that can be used to assess the quality and
convergence of such simulations which is crucial to obtain reliable results.
The basic ideas of a step-wise evaluation are exemplified for the study of
nucleation in several systems with different complexity, providing a general
guide for the critical assessment of RETIS and FFS simulations.
