I stayed at the Park Hyatt for a business trip, and I had not selected the hotel myself. Nonetheless the hotel impressed me with excellent customer care, and I will happily return next time I'm in town.
The hotel itself is located halfway up a high-rise building, starting as I recollect from the 42 floor. Travellers susceptible to vertigo should look elsewhere, but for everyone else the hotel provides outstanding views over the city, and (on a clear day) to the mountains in the distance.
The rooms are more spacious than common even in hotels of this class, and are well equipped for business - the desk provided power sockets for plugs from several continents, as well as USB power supplies.
The rooftop restaurant offered an interesting mix of Western and local breakfast options, and while I cannot judge how authentic the latter were, I can confirm that all was cooked to an excellent standard.
In terms of location, the hotel is a 30-45 minute cab ride to the airport (very traffic dependent, so allow much more before a flight - traffic can be terrible in Hangzhou!). It is also located above a shopping mall featuring mostly international brands, and is also connected to a subway station. This makes it easy to visit local tourist destinations if you have any spare time during your visit.
Finally a special call-out to an assistant manager, Mr Clement Lebaupin, who saw me returning from a few hours of tourism before a long-haul trip back to Europe. Knowing that it was fairly humid outside, and that Id already checked out of my room, he kindly offered me the use of the hotel fitness centre to take a quick shower. This definitely made my trip home much more pleasant, and was a typical example of how the staff really make an effort to put the customers' needs first. Overall a great hotel!