Planning a trip to London for the first time, using points for my stay. I'm considering several central London locations, the number of points are all equal. I'm considering the London Edition, both Grosvenor properties, St Ermins, CountyHall, Marble Arch & St Pancras. Important to me are location to tourist attractions, location to public transportation, concierge lounge offerings and clean and quiet rooms. Anybody have recommendations on past stays? Have I overlooked a place I should consider? Or have insights into any of these properties?