Getting out will take about an hour. I wouldn't recommend the W with that kind of timing. You'll end up paying about $500 hkd for a cab each way or $90 per person for train each way. Plus you won't get to enjoy anything. Between the hotels I would stay at the regal. Will cost you more or less the same as going out to the city plus all the associated hassle. If you're flexible, I would stay at sky city Marriott at the airport. Will cost around $150 usd and is right at the airport. Great hotel for overnighter.