The description from the website wasn't exaggerating. It's a wonderful property that creates a "old money", luxury feeling. Wooden floor with (seemingly) high quality carpet here and there, very comfy bed with fur blanket on top, a good-sized balcony with a real fireplace (which the staff comes and sets it up for you on request) and full set of toiletries from Hermes.
I do not believe any upgrades are done here; neither there is much Marriott footprint. Stayed a few times with last time in May 2018.
To me, it has always been ~300 euros well spent but YMMV.
