Why is Niihau one of the top dive destinations in Hawaii?

[qwimjim]

Niihau is all that and more. Its seasonal , May through October. The trip over takes an hour and a half...easy crossing. The trip back can take 2 hours and on some boats alot of banging. I have dove Palau and Niihau is still on the top of my list. No risk if you go with a reputable company. They will cancel if the conditions are not safe. There are great drift dives but not all the sites have current. Again its worthwhile to get with an experienced dive company to fully enjoy Niihau.

How does Niihau rank up there with Palau? I just ask because I've never read anything but rave reviews about Palau, but one person on here said Niihau was no better than the local dives on Kauai, and that those dives were nothing special and that the diving was much better on the Big Island.

So I'm confused as to how two people could have such differing opinions of the place