As a platinum member, you can only receive a RC upgrade with a coupon. Since u are already in a RC room, what type of an upgrade are u looking for, a suite? It cannot hurt to ask, but as far as entitlement, Platinum does not get guarantee u much.
I was at this hotel in June. As a Diamond, they guaranteed me a room during a fully booked period, upgraded me to a Gold Passport floor (RC was full for a convention), and gave me full RC privilages. They also gave me discount coupons for the Breakfast buffet, and invited me to a GM cocktail hour.
I found the Spa and pool area great, as well as the RC. They had a nice breakfast spread, with cereals, breads and pastries, cold cuts and salmon, and fresh fruits. They also had a nice cocktail hour and evening desserts.
The gold passport rooms were quite standard, and can't comment on the RC rooms.
The staff is very friendly and competent, I think u will really enjoy your stay there.