Obviously FS/MO/PH are the most well known to the general public and also the biggest players in the industry. I however always feel these kinds of questions are difficult to answer because in my opinion you should not compare entire chains with each other as one can always argue one bad apple in the midst where guests receive consistent bad service, has an outdated property or just a bad location.

Although Aman is obviously the industry leader, what about GHM, COMO, Six Senses, Anantara, Oberoi, O&O, Maybourne hotel group (3 hotels but nevertheless a "chain"), Constance, Leela and not to forget Alila?

One could argue that FS is the industry leader in business hotels and Aman in the leisure industry, however I still feel this is too much of a generalization as there are hotels belonging to the chains that I have just named that would blow many Amans or FS away.

Perhaps we could calculate the number of good hotels within a chain, compare it to the total amount of properties they have and come up with an percentage indication, but what would it really benefit anyway?

Hypothetically speaking, let's for arguments sake say that MO decides to open a rooms only property in Mauritius without a beach front, where you have the Le Prince Maurice that belongs to Constance. Now, let's assume MO will get a better percentage than Constance in our calculations, there will be people expecting the MO to be better then Le Prince Maurice which is obviously not automatically true.

My point is, you should pick a hotel or resort on the needs that you require at that moment, what suits you and where you feel the most comfortable. You will only learn of these points by researching the hotel's facilities and review the feedback from others who have stayed there. Not by going to a website, find which hotel chain is rated higher and blindly pick the chain just because of a rating based on opinions of somebody else.