Bruce,
Since when is Sheraton not a luxury hotel? The hotel's website describes it as "Los Angeles's ultimate expression of urban sophistication and contemporary comfort" (see http://www.starwoodhotels.com/sheraton/search/hotel_detail.html?propertyID=344 ). Even allowing for hyperbole, it sounds like an upper end hotel. Also they did a renovation last year, and it is now "stylishly redesigned."
I don't know where you're used to staying. If your basis for comparison is the Beverly Wilshire or the Four Seasons, then I could see Sheraton not being luxury. But for the average traveler, I'd say the breakdown goes something like this:
luxury