As a recommendation by F Javier Luque, we can find here a very fresh paper with comments abut the accuracy of binding free energies in solution.
Possibly worth to most of us:
Predicting accurate absolute binding energies in aqueous solution: thermodynamic considerations for electronic structure methods
by Jan H. Jensen
Published in Phys. Chem. Chem. Phys., 2015, 17, 12441
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