Art, the reason I recommended the "Up Close" tour is that I assumed you aren't visiting alone. But I just re-read your message and you don't mention whether anyone else will be with you. Non-space-freaks, especially kids, may be bored by the "Then & Now" tour. But enthusiasts will, of course, enjoy it. You'll like either tour, I suspect. I haven't been on the "Then & Now" tour for a few years. I tried to take it about a year ago, but it wasn't offered the day I was there.
I ran out of time, but I was also going to suggest that you'll want to take advantage of the "second day free" offer on the "Maximum Access" passes. Without the guided tour, KSC is an all-day experience. Whether or not you take one of the guided tours, get to the visitor's center early. I'd suggest, in addition to one of the tours, you sign up for the "Lunch with an Astronaut" lunch (another extra-cost thing, but worth it - see
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Not only is the food (marginally) better than available elsewhere in the Visitor's Center, but you are treated to a presentation by an astronaut and, usually, an autographed photo. You could take the guided tour one day and do the lunch the other.
My wife and I visit KSC several times a year. Usually we go to "have lunch" with a specific astronaut. Most of the times the astronauts are one of a few regulars such as Sam Gemar. All of the regulars are excellent speakers and I'd recommend seeing any of them. But every once in a while, they'll have other astronauts including ones from Apollo and earlier. That's when we usually visit. We also attend the Astronaut Hall of Fame induction ceremony each year which is attended by dozens of astronauts.
My favorite attraction at KSC is the Saturn V Center. They've created a terrific presentation and there's nothing like walking under a real Saturn V. I also can't get enough out of the 3D Imax films - especially the space station one. We also enjoy spotting widlife while riding the bus during the tour. One time, our bus had to stop because a very large alligator _ran_ across the road - an amazing site.
Oh ... as an aside ... sometimes people are confused the first time they visit KSC thinking they have to sign up for one of the guided tours to take a bus to see the shuttle pads and other things. That's not true. A bus tour is included with your regular ticket that takes you near the launch pads, to the Saturn V center, and to the International Space Station facility. The "Up Close" tour gets you closer to the Vehicle Assembly Building, launch pads, and other interesting sites with a tour guide.
-- Roger