Just to update the Mandarin Oriental bit.....
The Excelsior Hong Kong give me 500 / 750 Avios per stay, depending on room rate and type (though I'm still to work out where the line is between the two).
Don't get any of the other bonuses due to Gold card, though (but they do often upgrade me anyway, and give me small gifts as a regular guest)
Caveat: I get a good rate at the Excelsior and sometimes they don't give me points, others they do.