I haven't stayed at the Marriott in Kauai, but I have been at the Hyatt while my friends were at the Marriott at the same time. We both hold the highest status in each of the programs, and we spent time in each other's hotels. I thought the Hyatt was much nicer, and my friends also thought the same way. They really did seem quite jealous of the diamond treatment we got at the Hyatt (the lounge, spa, etc)