Since the SPG program has integrated Sheraton and Westin brands, I've had my bed-type + NS res. honored in all but one property on one stay -- a Westin and that was a very late c/i. The excuse was "we didn't have your SPG # in the res." When I asked to speak to the MOD and showed the Starwood booking printout with my #, all of a sudden, a reserved room type was "found" in hotel inventory and the manager made things right. His initial position was that it was a computer problem in getting res. info reliably from *wood. My answer was that if his property was having computer problems of that type *wood needs to know about it ASAP because its corporate HQ was going to be calling when increasing #s of Plats get stuck in smoking rooms on the 3rd floor, contrary to their res. confirmations.
Despite this stellar record of Starwood compliance, I do what EnvoyBoy does if I am going to arrive late and just call the property, mainly so I don't lose any u/g that may be available.