The gent who used to post as Wyvern had a shedload of hours in piston and turbine helicopters of all sizes, and is an ex CFS examiner. He was good enough to mentor me as a baby display pilot a fair number of years ago, and is an utter gentleman and brilliant instructor.
He elected to ground himself a few years ago due to age and some personal medical concerns he had, but I am still in touch with him occasionally and whilst I'm certain he'd not wish to try displaying again, he'd be a superb mentor.
If that's of any use, PM me and I'll try and put you in touch.
G