In many ways this is an excellent hotel. Hotel staff are willing and plentiful, hotel is well appointed, laid out and has a great position. Lobby bar is cool, bar at top is cooler. Penthouse pool is something to behold and never busy. Food is ok by western standards but very good for Asia. But there is a but, and its absolutely huge.
The air quality in Shanghai is simply terrible. For most of my stay it was classed as Unhealthy, occasionally Very Unhealthy. The foul air and its attendant particulates pervade the hotel (and I'm sure all other hotels). I've got a strong constitution but have been coughing and wheezing whilst hear and have simply been counting down the days to the trip is over. My advice is steer clear until the government cleans up the air which will take a number of years.