Just like most things in life, there are exceptions to everything! My daughter's show bunny was an exception and her current bunny is also and exception! Carrot, her show bunny was raised in the house, NEVER sprayed, and was the most meticulous litter box using bunny EVER! He rarely humped and was an awesome bunny! When retired from showing...I decided not to subject him to surgery as he was older...a decision I regret as we lost him to a testicular tumor last fall. On the other side, we have my daughter's current bunny, Cheerios. Cheerios is 9 months old...he was the sweetest, cuddliest, most friendly bunny UNTIL we had him neutered in March! He is now the "monster" bunny who puts my daughter in tears on a daily basis with his chewing and biting, and all around undesirable behaviors.
So for us, we have had both exceptions...but we have also had the typical..like mentioned in comments above....our female, Funfetti...was spazzy, difficult to pick up, difficult to litter train, and she sprayed ALL the time and EVERYWHERE!!! She was spayed in March and ever since, she is one of the sweetest, cuddliest bunnies...has NEVER sprayed again and is meticulous about using her litter box!
Having said all that, having dealt with exceptions...and given that we love bunnies and we don't show anymore, for me, the risks of not spaying and neutering are too high! So I will always have my bunnies spayed or neutered...for health and behavior.