Taxis and Uber are a huge pain in the city, especially from/to Laguardia Airport in the evening, and with the UN General Assembly starting Sept. 24th, it will be insufferable. I strongly suggest the SBS bus (the Q70, not the M60)/subway connection, but please note that the F train will not stop at 57th St. until the end of the year due to construction. From Jackson Heights (transfer point from the Q70) take the R train to 57th St.