I have the M40.2 on demo and heard the Graham once and my findings are different. The M40.2, with it's dedicated mid driver, has a far more out of the box, natural mid band and an ease and relaxed nature.

I have done direct A/B demonstrations of the LS3/5A v P3ESR and LS5/9 v M30.1 and on each occasion the customers have preferred and bought the Harbeth versions.