Fathom is one of the best playing machines from any era. it is in my "Top 5 of all time". It was subject to being a "cookie cutter" SS for many years, as they are rare and have a stunning artwork package. I think Bally released a few great games between 1979-82 - Centaur, Fathom, Medusa, Eight Ball Deluxe and Viking.
Getting slightly off topic but what are the other 4 in your All Time list...