Stayed here recently as platinum and enjoyed it, with some minor annoyances.
Quick pros and cons


PROs

Inside the airport at terminal 3, on landslide, where the general public enters and exits.
If you arrive at terminal 3 you can push the luggage cart from the airport belt where you pick up your luggage, past customs, and all the way through the airport straight to hotel reception without stairs or elevators.

Nice large swimming pool on level 3 with sun loungers and free water.

Was given a upgrade to a large corner room.

Late check out till 2PM granted without problems.

Friendly staff.


CONs

Breakfast costs 25 SGD plus taxes and "service" charge coming to 29.50 SGD per person.
Breakfast buffet has asian and western food, plus fresh fruit , all of which tasted nice.
However, there was a lot of food residue under various tables at breakfast. These were tables that had clean cutlery and clean napkins on top and were ready for new customers. I told a staff member who was clearing plates from occupied tables, and she said that a different person cleans under the tables at a "later time". She didn't do it herself, nor did she get anyone to come do it. Made a bad and unappetising impression while eating. Also there was no one serving at the noodle station.

Getting a taxi to come pick you up at the hotel entrance incurs an extra booking fee. If you walk back 5 minutes back into the main airport building, you can join the normal taxi lines and get one with no surcharge. However ALL taxis leaving the airport have a 6 SGD (or 8 SGD at peak times) surcharge.
See here:
https://www.changiairport.com/en/air...e-airport.html
and here:
https://www.channelnewsasia.com/sing...jun-30-3155176

Despite being at the airport this hotel is as expensive as a 4 or 5 star property in the city centre often asking for more than 400 SGD per night. It seems overpriced for what (and where) it is. Unless you have a very early morning flight, you may want to use your money for something a lot more central. If you must stay and have enough IHG points, this is a place to use them.

Windows can NOT be opened for fresh air.