I had the snip immediately after having our 3rd (our fantastic bonus for being good) She is 8 years younger than her brother and sister.
If your absolutely sure that you dont want any kids then I beleive the snip is a far better and safer way than for a histo.
Although of course life throws a few curve balls, my wife and I split after 23 years of marriage and I have now met another wonderful woman. My point here is things change and the snip can be reversed. I met an old friend over the weekend and he had his snip reversed and he is now the very proud father of and 18 month and 3 year old boys. But if you ask me he must be mad to have young kids at 50.
About the op :- It does NOT hurt. BUT you must rest thoroughly after it. Go to bed and stay there for at least a day.
Good luck
Mark