We stayed at the Westin about 7 months ago and enjoyed it (on points for an anniversary trip). Great location! Did not find it to be 5 star but still a solid 4.It is a bit worn inmost areas but nothing that ruined our trip. We were left both a bottle of pretty good Champagne as well as a scrumptious dessert tray in our room congratulating us!

If you compare the base rooms at the Westin they are way bigger than the StR's base room. You really need to go all the way to a junior suite at the Regis to get the same size space that you would have at the Westin's cheapest room which was really quite nice. Something to consider, So if size really matters be ready to fork for a lot of $$$ if you really want to stay at the StR. We did walk around the regis and it was lovely and a bit more upscale for sure over the westin which in its own right is a lovely hotel. If you have the bucks and can get a jr suite go for the St Regis!