Definitely go directly to the Park Hyatt, and I would highly recommend taking advantage of the hotel concierge's email offer of having a Hyatt representative meet you at the air bridge upon leaving the plane to take your bags and expedite the border patrol line. Also sign up for the Hyatt S class Mercedes to pick you up at the airport as the Hyatt rep will phone the driver and meet you as you leave customs. The entire service cost about $110 with tips, is added to your hotel bill so no need to worry if you have no VND, and well worth it as the taxi line can be daunting at SGN at night, especially after a day of flying. I was off the plane, through border patrol, and arrived at the hotel within 25 minutes.