The Q2 insertion quadrupoles for the High Luminosity upgrade of the LHC are currently being produced and tested. The test of the first units provides valuable information about the field quality of superconducting accelerator magnets built from Nb3Sn coils. This paper presents the results of the magnetic measurements performed on the prototype and series magnets with emphasis on field quality and field repeatability. The stability of the integral gradient is analyzed in view of the final installation in the machine.