I picked up a Twister in a package deal recently and man the air balls were CRAZY! Even with the back legs cranked up it seemed nearly every missed shot launched a flying air ball.
Today I replaced the flipper coils with a pair of used 23-900 coils I had in my parts box. Night and day difference! Sure, can still get an airball once in a while, like a direct hit off the drop target. But the game is totally playable now where before it was a shitfest of airballs constantly.