If you are not planning to use him at stud I would have done it at about the 2 year mark anyway. I am a firm believer in the need to spay and neuter so if I believe in it I have to also do it. My two girls are spayed because they are not breeding quality and would lessen the breed if they produced any offspring and if you feel the same way then getting your boys who-who's removed wont be too terrible of an experience. If he has never used them he wont even miss them and it will make him a bit more manageable. It wont solve the issue completely, but remove the hormone blast and some carefull training and he will make you proud.
Hally, The Olden Golden 12/5/1999-
Indi, (GSD) 8/4/2011-
Dixie, (GSD) 8/11/2011-
Sassy, (Rottie) Born 10/9/1999-6/12/2006 RIP