Tried this on one of my drain-monster EMs, a Gottlieb Flying Chariots.
Scores
768
458
1053
592
649
489
557
590
659
640
Average 645.5
Median 616
Standard Deviation 168.23
CV 0.26
High Score 1053
Low Score 458
I'll definitely have to try this on some of the other machines I have access to. I suspect a trend toward inconsistency will appear
Dave