From the overall good agreement we find between the results calculated using the TI and FEP estimators we remark on the conclusion of previous studies , which compared Schrödinger's FEP+ to other TIES based alchemical methods revealing significant underestimation of the free energies when using FEP+. In this case, there are several sources of difference in the methodologies, including different force fields and FEP+ use of so-called "enhanced sampling". Since the present study finds good agreement between TI and FEP estimators it is clear that the remaining differences require further work to unravel these significant differences, although the proprietary nature of FEP+ does not make any such study straightforward.