Who are these "Best of the Best?"
They are prior military pilots (at least in the US).
Not really. I've met more than a few who didn't seem to get hot and high work or be able to plan ahead for limited performance, having been used to the capability of losing an engine and still climbing out or continuing.
One could say that having to start from scratch in a machine with practically no rotor inertia and very limited performance forces one to plan ahead just a little more.
It comes down to the individual. Not to the place where the primary training was done.
This translates into having flown so many hours, under so many condions at such a very high pucker factor that a hair-raiseing flight for for the 'common pilot' isn't even worth mentioning in their opinion.
Military pilots tend to have lower overall hours than many civilian counterparts in many cases, given the same time in service or time in a helicopter cockpit.