Compare to other cities in Asia, hotels in Manila are expensive when looked at quality/cost ratio. In general, expect to pay more, for a decent hotel in Manila, compared to cities like Bangkok in which you can pay 50USD and stay in a very nice hotel. Maybe it is because of the high taxes.
In general hotels are also older in Manila then other Asian cities, even the 5-star ones. The Diamond, while not the best hotel I stayed at in Manila, was a very good hotel.
The rooms were upscale, modern and clean. The internet was free, cable line in the room and wifi in the lobby. The Gym is decent and staffed. Breakfast was also very good. It was a large buffet with Asian and Western choices.
Located in Malate, near Roxas Blvd (which has a lot of nightlife) this hotel is not far from the airport. The hotel is right next to the Hyatt and the Pan Pacific Hotels. However I prefer Makati to Malate simply as there are more things to do there and it is more visitor friendly.More