I've written about this movie before, but I did check and this trailer has been pulled from the original post way back in time. I did make the Fiends a "monster of the week" as well, see this post for some cool pictures. But dang this movie is cool and so disturbing at some points.
It's also surprisingly gory, and the sound effects are quite amazingly gross. I never saw the entire movie but that sound lingered with me for many years. It's just that memorable.