They are neat. They are used a lot in prototyping of a part before they go through the first article build just to make sure it looks like they want, works like they want, etc...
There used to be a company directly behind mine that had about 5 of those and that is all they did. I believe they moved across town to expand. I used one back in 1999 to make a prototype of the final product from the mold I was going to make.