I second the suggestion to take 2 taxis. Singapore has excellent taxi service. It's cheap (as stated) and they use the Toyota Crown taxi that you also see in Hong Kong, so you'll have plenty of room. The taxi stands at Changi are well ordered (as you would expect in Singapore), and the trip to the SIN Hilton should take about 20 minutes. You can also pay by credit card and the driver won't hassle you like they do in NYC