I asked my wife if we could visit this attraction and she said (and I believe I married her in anticipation of this moment), "Sure!"
Boy am I ever glad we went. Free admission, and very very cool. We went on the $8 tour of Ellsworth AFB and the missle silo, and it is an absolute must see!
After the second hour, my wife was starting to get bored, so we left, but i could have easily made at least 1/2 day out of it.