aWful
Having stayed at the W in London and Maldives, this was an easy call. We thought that we knew what we were goIng to get as both London and Maldives gave us the WoW experience. Sadly this was not the case in SF.
On arrival at about 6 pm there was one person on the reception, 5/6 desks and one person. Pleasant enough welcome and valet was good to room.
We booked, by Expedia a 'Fantastic Corner room' at $365 whereas booking direct would have been $565. Having stayed in the same named room in London, there was absolutely no comparison. The London room was Fantastic, not so SF. Basic to the extend that the shower was over the bath with a plastic shower curtain! 4/5 Star it was not. Apart from miniscule shower soap and shampoos there were no simple things such as a shower cap, buds, slippers etc. All the stuff that you would get in a 3 Star hotel. Two worn bath towels, we had to call for all of this, very poor.
The shower did not work and when the engineer came by to repair he explained that 'they were all like this' and that he had just repaired two others in the past 30 minutes.
Great bar, great cocktails but we did not sleep or shower in the bar, so no good. A big big let down from the W. 
Would not go back.