Just like GPS or WiFi phone performance is affected by ones surroundings. If there is minimal or no towers, congestion or obstructions reception will suffer. There are millions of S3's in service around the planet and very few complaints in relation to the installed base. Market share seems to indicate Samsung is doing something right.
You can flash different radios that some claim help isolated issues. How one would ever test that is beyond me. Way too many variables. Funny thing is that some who have taken the MD3 update claim the phone is now worse.
