RE: Sonar on FFS – I fish myself and have found the enjoyment of FFS first off but don't believe it's the best direction for the sport.
All sports for the most part have advanced technology's out there that the highest level aren't allowed to use. Look at the major leagues and wood bats, golf and the golf ball, drivers to name a few. Just because it's produced doesn't make it a shoe-in for the highest level.