This is mostly a safety tip for people who are traveling to Salt Lake City to use the wonderful research facility, The Family History Library. Before you go, use the online catalogue to see the films you want to use. If any of them say VAULT as part of the call number you need to know the following. The Vault is an off-site facility where films are stored. It takes at least two business days (sometimes more) to retrieve films from there. Newly filmed documents are automatically put there. Once retrieved to the Salt Lake City site, they remain there.
So, when I began using the 1869 Hungarian census for the towns of Tura Luka, Vrbovce, Castkov, Sobotiste, and Myjava, I was the first to do so, and all of these films were off-site. I was there for a week and got some, but not all returned to me. It would literally take me three separate visits to get all the films on site and use them. Some of that was my fault (not knowing the difference between Castkov and Sobotiste was partly to blame), but much of it was the retrieval process. All of these films are now in the FHL facility. Your village may not be.
I'm not sure how it affects borrowing films to a research center elsewhere in the U.S. Certainly, I'm on top of knowing these same towns have their parish registers now filmed and I've begun borrowing them. It seems OK thus far. However, I borrowed the Myjava films and I still note that the catalogue says VAULT, so the films may circulate to other centers and yet not be in Salt Lake City. It is best to call ahead of time and have those films retrieved. If they don't do it on the phone (it is dependent on the mood of the person on the other end, I've had one success and two failures), get a friend to go over and order them in person before you arrive.
There is nothing worse that being excited to do research and find out you can't due to some bureaucratic snafu.