Reviews, weighted by how many. A 5.0 from nine people is not better evidence than a 4.9 from 332. Across the twelve listings there are 1,952 reviews, and 332 of them sit on one flight. When we call something the best helicopter tour Maui sells, that asymmetry is doing most of the work.
What it does that nothing else does. A listing that lands somewhere unreachable, or removes the glass, or crosses a channel, is offering something the others cannot match at any price. A listing that flies five minutes longer is not.
Cost per minute, as a tie-breaker only. Useful for comparing two scenic flights against each other, useless for comparing a scenic flight against a landing.
What the reviews complain about. Across every helicopter tour Maui listing here, the complaints are about weather rebookings rather than about the flights, which is a good sign and also a warning to leave a spare day.