What is the best route to get out from Pudong Airport(arri time 8pm) to Radisson Blu Pudong?

Oh, you must refer to Radisson Blu Pudong Century Park, right?
Upon landing, you can take the Maglev train at the airport, get off at Longyang Road Station. Then take subway line 2 to Science & Technology Museum Station, Exit 6.
Or you can take subway line 2 all the way to Science & Technology Museum Station.
After arriving, take a taxi to your hotel directly. The cab fare is about CNY 15.

Hi Jeff,
Thanks for your advice. Please let me know, in Maglev train they would allow to carry check-in bag luggage weighing around 30 kgs?

Yes, as I know, you can carry it.