Fright Lane tends to vary from Friday night to Saturday night. If you go on a Friday night and are lucky enough to catch the local high schools (Mason, Kings, Little Miami) with home football games, typically you can get through the majority of the haunted houses. Saturday nights are crazy and without Freight Lane, is almost impossible to get through all of the houses.
It is a hole punch method like mentioned in an earlier post, you get fright lane for each haunted house one time, with the option of a "free one", that way you can go back and choose which ever house you want to do a second time.
My wife and I go every Friday night, and almost always buy fright lane, mainly because we both like to move as quick as we can due to baby sitter restrictions.
Also, an added value with Freight Lane is the golden key that comes with it, which gives you access to secret rooms in select haunted houses. Not anything major that you would miss out on, but a nice addition for sure.