Nice, but not great. Only a few cars are actual Hollywood cars. Most of the "Hollywood Cars" are poor replicas. The Liberace cars were interesting and seemed to be taken care of. The vast majority of the other cars are not maintained. As in washed, dusted, polished, etc.
It was a good time waster, but I would not recommend going out of your way, like I did, to see it. Cost is $20. They offer a $5 discount on their website. I was in and out in an hour.