Great Stay
Stayed in both the Marina and Bay Towers last week. Rooms are bigger in the Bay Tower but both were nice. 
Shuttle arrived at airport within minutes and trip to the hotel only took a couple of minutes. Check in was a breeze. 
Beds were comfortable in both my rooms. The Marina Tower has a Starbucks, Nicer Pool, and better restaurants. The Bay Tower seems a little quieter with bigger rooms. 
Would get 5 stars if the gyms were open, but gyms in both towers are being remodeled. Both should open within a month.