A few months back, I stayed at the Westin and had a meeting at the Sheraton. I was upgraded beforehand (no SNA's) to a nice high suite overlooking the runway- my request. No problems at all with the stay. The Sheraton is just across the freeway and is a larger and also nice hotel. I would (and did) make my decision based on price, as there is really not much difference in the 2 that I could ascertain.