Any thoughts on using RedWeek?

We’re trying to book a hotel in Maui for the middle of this summer and lots of the ones we’re looking at are fully booked. But we came across the RedWeek site and saw many options that are available.

Has anyone had any experiences (good or bad) with using that site for booking? I think signing up for that site costs $19, but it would be worth it for sure if the listings are safe.