Great question! Opening doors to value systems, philosophical discussion, birth control, decision making, social responsibilities, and oddly, my 'con' pain.
Just go with me a moment. I am making myself vulnerable. I am 57, and have had many an opportunity in life. The one thought to my mind is 'birth control' in those social interactions. Convenience may not be at hand, sort to speak. Those opportunities of mutual consideration could be resolved with a vasectomy.
Or, I'm married. I am 34. We have decided not to have more children. The easiest resolution is a vasectomy.
What is common in my 'male' view is the associated pain. Yeah, snip-snip, go home, discomfort physically for a week or so, pretty much permanent. But, the pain may remain.
Or, I'm 19 and hate kids. I don't want 'em ever. Again, snip-snip. But, oddly there is still pain.
Simply the pro is ease, convenience, pretty much permanent, and socially responsible.
The con for me is 'pain.'