It's interesting to read the difference of opinions between the ppl or amateur pilot, who fly for free or whenever they can or can afford to, and the commercial or professional pilot, who gets paid to fly whether they feel like it or not!
Far longer ferry flights have been undertaken by single piloted helicopters in such illustrious machines as the Bell 47, without any modern benefits, and of course more modern machines with all the latest gismos. In other words long flights are no big deal in general terms. All that is needed is a reliable helicopter, the knowledge to flight plan correctly, good weather forecasting, the ability to calculate fuel usage to refuel locations, maps that are half way accurate, a bum that doesn't go numb and the ability to stare out the window for 10 hours a day.
I've flown in the Antarctic in a 206 and as long as one keeps a beady eye on the weather and is aware of how to combat white out problems, then really it is no big deal. Obviously like in any type of flying, you can get caught out and that is where experience and common sense comes into it.
I don't know this pair but let's face it, they have a new machine fitted with all the latest gismos, plenty of money, should know how to flight plan and refuel and, hopefully, plenty of common sense when to chicken out if it should go to worms! As they are spending months doing it and not weeks as a company would, then getting a numb bum should not be a problem!
As for getting a SAR call out or having to get rescued by other means, so what, numerous people have to get rescued, that's why there are rescue services. It is far more enjoyable doing a real rescue than spending hours tossing out a wooden dummy to practise winching up, so I've no doubt that a rescue crew would enjoy the challenge and if they can't succeed, then so be it.
To any ppl/amateur pilot this would have to be a great adventure. For me after 42 years in the helicopter business, it would be a bore. But then I'm not doing it, they are and I wish them well whether they succeed or not.