We stopped here on a trip 2 years ago....Nice selection of A/C, BUT, many of there were in horrible states of disrepair, quite a shame really. The stuff inside was OK, but the models I saw in the showcases were in really bad shape. Plenty of other sites in the area(Rushmore, Devil's Tower, Deadwood, Custer Park, Badlands, Black Hills, Missle Silo tours), but I wouldn't make a special trip just to see the museum.