There is no credible basis to believe the Piorun has a better seeker. Piorun's seeker uses a design similar to obsolete variants of the Stinger. Modern Stinger

There is no credible basis to believe the Piorun has a better seeker. Piorun's seeker uses a design similar to obsolete variants of the Stinger. Modern Stingers share a guidance package with the AIM-9X Sidewinder and, unlike the Piorun, have dual mode imagers that work in both IR and UV which makes them impervious to flares.