In view of the success of MIM3 methods using PM6+D3 as the lowest level of theory (and B97+D3/ 6-311++G** as the highest), it is worth considering whether alternative semi-empirical models would fare better. In previous work on enzyme thermochemistry, 25 supersystem correction computed using either HF-3c or HF/6-31G afforded nearly identical results. The performance of the PBEh-3c model, 147 which uses a double-ζ basis set rather than a minimal one, was also comparable. As such, it is perhaps more beneficial to work on ways to reduce the cost of MBE(3) calculations via screening, rather than cycle through a long list of lowcost electronic structure methods that could be used for the supersystem correction, with no clear physical reason why one performs better than others. ).