I had Cody done at 7mo. It didn't seen to change his attitude at all!! He's 9 1/2 has slowed down but still thinks like a puppy! He too is a lab mix at 100 pds. He was once about 125 but only because I was constantly giving him people food, tho I denied it at the time (selective memory) Cody hates all dogs, he's very territorial but the answer to that is constant training (he mostly ignores them now esp since I learned to be alpha) He also "forgets" to lift his leg at times and squats but I don't know if that's due to neutering (right, Tucker?) My cousins 8 yr old Corgie was just fixed as he started to develop prostate cancer, but he's ok now. Hmm....implants?? You mean..... really??? Sandra..getouttahere! Maybe a Freudian substitute for human male inadequacies?? HA!