With the lounge and the nice views, I think the Towers is excellent value for points. Haven't stayed in the main hotel yet.

No, it's not the best in Hong Kong, or even close to the best Sheraton in Asia for that matter. And yes, the W is a very impressive property in terms of the hotel itself. But considering that the W is much more expensive in both cash and points, with (in my personal opinion) a much less convenient location, I don't see the Sheraton as a noticeably inferior choice.