i recently bought this, as the remake has just been released and i wanted to see the original before the remake, so i could compare them and so :).
This film is great, and one of the best slasher movies ever. i would recommend it to anyone who is in to the horror genre. it is filmed very well with great camera angles, which adds to the suspense and tension of who the killer is.
One more thing, i knew who the killer was before i'd seen the film, but if you don't know who the killer is. DON'T READ THE SYNOPSIS ON THE BACK OF THE DVD CASE. it tells you, which is stupid, and i imagine being very frustrating.