GH: Batting almost 100% upgrades this year, fabulous suites with huge tubs to soak in. The workout facilities and hot tub / sauna / steam room are great. Awesome staff.
Olive 8: Rooms are average, no upgrades this year. Pool is nice, hot tub is not hot enough. Crab benedict for breakfast is one of the best things ever.
If you want a better room as a Diamond, choose GH. If you want a really good breakfast over smoked salmon / common contintental, choose Olive 8.