Thank you for your answers. Yes,usually we have a better ratio FF/TAS in a OEI configuration, although it's not true for all of light twin engines helicopters (i.e SA365 C ) and by experience, with a heavy S76A++,in "hot" condition,TAS falls quickly around Vy to maintain 0 Vz and the ratio falls quickly on favour of AEO....but so many other factors are involved.
It's true that the S76C+ does a very good job in regard with payloads and speed at above ISA conditions ! besides this, it also provides a very good every day serviceability.