When I visited the Island in 2004, it was very quiet. At that time, there was a lot of LTR being used. Not certain if Public Safety was using it not. But it was very very quiet to me. Although, I was not in the tourist areas, rather I was in Paia, HI, which sits on the east coast of the Island.
I did see in some reading not long ago though, that Hawaii, including Maui, was going to undergo some radio changes, so this may have happened, or happening at this current time.
On thing I did scanner was air and martime. Maritime was especially cool since I'd never heard it on my scanner before, and it was a long time ago that I was in the Navy. Not being an RM though, I never saw communication equipment, beyond the pay phones stationed through the ship or HTs.
Ahhh Maui, the Island of paradise. How I long to move there, and will when my mother passes away, then I'm selling it all, and moving to Maui, and live with my niece.
Happy scanning!