Do you think his push for 50% custody is primarily about not having to pay child support? Is your income close enough to his that you could afford to forgo child support? It's often not a wise decision financially, but some do decide to forgo child support in return for increased custody.
Of course, at 14, the courts would go along with your son's wishes and only order perhaps every other weekend visitation if he didn't want to be at his dad's 50%. Once the 12 year old is 13 I believe the same would be true in most places.
But also it's likely that your H won't follow through on 50% custody for long - after all, it's not like he's been spending a lot of time with the boys in the last few years anyway.
