Antennas sticking out of an aircraft obviously increase profile drag, but the folks who design antennas have done a lot to improve aerodynamics: High performance aircraft can have antennas mounted inside of fiberglass components like wingtips, and flush-mounte antennas are available for transponders and DME equipment.
For slower light GA aircraft more aerodynamic antennas are also available (e.g. blade-style transponder antennas are available which produce about 80% less drag than older spike-and-ball style antennas), measured at 250 MPH.
Since the average light GA aircraft has a VNE below 250 MPH and isn't generally covered in antennas, how significant is the antenna drag on a typical light GA airframe? For example, would stripping the ~6 pounds of antenna drag from your average Cessna make an appreciable difference in airspeed?