Yes, I went there. Very cool place. Make sure you schedule in advance.
I was on vacation in the area, so thought I would make a pit-stop on the way to my flight. I called the day before and got no answer. I left a message asking if it would be alright if I stopped by for a tour. I never received a call back, so I called the next morning and finally got someone on the phone. They said that it would be fine for me to show up for a tour. I didn't think to get the guys name who answered. I showed up when I said, and everyone there said they had no idea about my visit. They asked who told me, and I told them I didn't catch the guy’s name that I talked to. Then I was told that they would not allow the tour because it was only two people, and there was a minimum of four per tour. I explained that I called and that no one told me about this. I also explained that I went out of my way to travel there. They finally agreed to a thirty minute tour for double the price for both of us. I didn't mind to pay extra, but I was a little upset about the circumstances.
Again, very cool place, just make sure you call them ahead of time to schedule.