Pros: Spectacular views
Cons: A bit pricey
At first I was a bit intimidated by a helicopter with no doors, but it's the only way to go. We had no unobstructed views, the scenery below was crystal clear. Safety was paramount and the staff ensures you're buckled in tightly before you depart, so don't worry about the "no doors thing". My wife and I took the one-hour flight in August, a great time of year to be in Kauai. We were in shorts and t-shirts, I would probably suggest warmer clothing during the cooler months. Forget hats, but be sure to bring a camera! Our pilot Gary was very accommodating and funny and gave us a tour of all the major waterfalls, canyons, and vistas you'll never see by car. My wife is very prone to car/boat/air sickness, but had no problems (a non-drowsy dramamine before the flight). At $170 per person (Aug 2003), we cringed a bit, but I would pay it again, it was definitely worth every penny.