Cheers for responses.

Spent more time with some calcs and found an excel sheet elsewhere on here which helped to confirm my thoughts.

Regards how believable the graph is...well that's always a debate with any quoted measure, even the biggest manufacturers make unachievable claims...but in general the shape or characteristic is helpful - It clarifies that holding torque is irrelevant in terms of dynamic performance and gives a clue as to usable range...

Motors have been ordered....we'll see how it goes...
Bally