My 10 month old westie has been perfect - high energy but obedient, playful, athletic, fearless, gentle, cuddly, quiet, will eat anything but doesn't beg for food. His balls finally dropped a couple months ago, but we've been too busy to get him neutered. I know owners do this to limit aggression and prevent babies, but his recall has been flawless and he has zero aggression, even to dogs trying to bite his head off. It's proven impossible to rile him. I don't want his temperament to change one bit... is that a risk with the procedure?