The flavor or smoked burgers is definitely enhanced when you sear the burgers after the initial smoking time. Some people even reverse-sear the burgers (sear them first then smoke the burgers at a lower temperature). The burgers should be smoked at 225℉ until they reach an internal temperature of 130℉, then seared at 450℉ for a few minutes on each side or until the internal temperature is 145℉ (medium).