The same way we saw challenges for Escape Nublar times, I think there should be a similar challenge for completing Soul Gem Quest with most remaining flips.
You start with 30 flips, then get 8 flips added for each shot made (bar the last) making a total of 86 flips available.
I believe the absolute best you could finish with is 79 (on a Prem/LE) with a few lucky slingshot bounces and dead bounces.
Hold right flipper before count starts to trap ball from kickout
Left flip to right orbit
Right flip to left ramp
Left flip to right ramp
Left flip to gauntlet ramp
Allow ball to pass upper flipper then right flip to left orbit on the fly
Left flip to captive ball
Slingshot into drops (had this happen a few times to me)
Left flip to Marvel ramp
Right flip to Tower
= 8 flips total.
A further flip could be saved with a slingshot bounce to Antman awarding a shot.
I played an LE on site for the first time yesterday and managed to finish with 55 flips remaining.
Anyone done better?