I can't stand the Olive 8. I think the personnel there are some of the worst I've encountered in the Hyatt system. The Grand Hyatt wins every time in my mind. If they are the same price then I'd go with the Grand Hyatt. Fantastic experience every time that I have been there. Rooms are lovely, staff is gracious, lounge was great (if you're a Diamond).
Realize though that both of these are 30 minutes from the airport so if you're doing a MR you may just want to grab a cheap place at the airport.