I recall the pin of my youth was a Firepower with drops in the 80's at Hornsby in Sydney's north.  Didn't pay particular attention to the drops because there wasn't the thought that they were anything unusual. I reckon the game has to be better with drops because the rules make more sense and are part of the "mission" rather than just bashing away and drops in general are fun.

I've been following this thread with interest as I have the drop assemblies to convert mine courtesy of a cheap ebay playfield from Pinballshed.