I have never stayed at a FS (yet) but the impression I get from anyone who has is that their service is beyond exceptional and unparalleled - not something you will usually see at even the high end brands of Marriott, Hilton, IHG, and Hyatt (i.e. STR, Ritz, WA, Kimpton, Park Hyatt, Andaz, etc). Not to say that these luxury brand properties never have good service or give upgrades; there are certainly many that do and I myself have had good experiences with, it's just that FS is much more consistent as a brand across all or most of their properties in making sure their delivery is impeccable.