Using NEQ, our accuracy criterion of ±1k B T was missed for only two systems, hp19 and hp9. Most likely because of its high flexibility and number of rotatable bonds, we could not obtain converged unidirectional results for hp19. Even with the bidirectional NEQ protocol, switching times of > 10 ps were required. For compound hp9 the unidirectional NNP→MM NEQ protocol with a switching length of 5 ps was barely outside the ± 1 k B T threshold. In addition, the unidirectional results for hp7 and hp18, while fulfilling our accuracy criterion, deviate slightly from the reference result. However, excellent results were obtained for other systems.