My encouragement is that if you are sure that this is a mutual relationship and that you would both be forgiving of the other's flaws and mistakes, then skip the pre-nup.
To be fair... who goes into a marriage thinking ANY differently? And if you are thinking differently... then why are you getting married?
I would bet that 96% (? or more) of people who are divorced... didn't think they would be. I'm divorced, and I can tell you, I NEVER thought I would be.
With that said... if someone has been married... and divorced... I think it's safe to say that a "well, anything can happen" can pop into one's head. Never say never... right?
I don't have anything of much value... but IF I ever got married again, I would go with prenup... that is if you can have a prenup that says, "If the man cheats on the woman, he is required to leave the marriage and pay for all debts incurred during the marriage". Of course, I doubt prenups cover cheating a-holes.
Anyhoo... GO WITH THE PRENUP. You have kids... and point out that HE gets to PROTECT his ASSESTS to. I think Paul MacCarthy's (McCarthy?) divorce is a prime example of why prenups are needed. Obviously to the extreme, but still. A prenup protects BOTH sides.
"Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather, to skid in broadside thoroughly used-up, totally worn out, and loudly proclaiming: WOW WHAT A RIDE!!!!"