It took some time to make the decision, but as he is a very-very dominant one, all dog trainers we have met suggested castration to make him more obedient. I was quite hesitant, as this is a surgical intervention (which is definitely less drastic in the case of males than for females - but still... taking something out that works properly?)
The big day arrived, the operation went well. He felt dizzy for a day after it, but after that, his appetite came back and he is feeling much better. He is really a good patient, he doesn't have a problem with wearing the collars (we tried two types, but the traditional white one turned out to be better for him), he is not in a bad mood at all.
So, probably it was not a bad decision...
Do you also do such interventions for dogs in your country?