I'm not a lawyer, but a couple of thoughts:

Emotionally, the right answer depends on how confident you are that you're in this forever (and how confident you are that HE feels the same way). How would you feel about this if he made a mistake (if you get my drift...)

Legally:
  • Laws vary from state to state...as Indysteel said, consult with a lawyer...but remember, a lawyer will tell you to get a pre-nup...a really good lawyer will understand the emotional side as well.
  • Divorce laws in many states favor the woman - particularly if there are kids (I'm not making a judgment here...just an observation)...this may place you at an advantage anyway
  • Some state laws allow for consideration of premarital asset composition in determination of post-marital distribution...thus allowing you to take out what you brought in.


Financially, you mention what you have...but does he have something of equal, but different, value that would equalize?

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.