My boy got done when he was 5, and it changed his temperament too, i cannot walk past another dog without him barking and growling now, yet before he was hardly ever on a lead whilst walking and had manners and was playful with other dogs.
I would be very reluctant to neuter any male dog i may have in the future.
However! All dogs are different and i know of dogs that have bin neutered, to be exactly the same as they were before. Just not mine