One thing Peter Liston didn't talk about on GWAE was the meter movement of Mystery Progressives he found in the USA. At Winstar in Oklahoma, for instance, he said he found 60 MP's. But my guess is he didn't find any meter movement higher than .5%. And that means those MP's are not that exploitable.
The thing I came away with from his book was that in the late nineties, in Australia, Liston was presented with MP's with five figure jackpots with 5% and 6% meter movement. That is super huge. That made those MP's very highly exploitable. That same golden opportunity never developed here in the USA.
My first encounter with MP's was at the Mandalay Bay opening. I think it was 1998. That opening was somewhat of a hustler's convention because so many exploitable games, the IGT Vision Series, the Williams games, and Silicon Gaming's Odyssey machines, were on the casino floor, along with these new fangled Mystery Progressive banks.
We quickly figured out the MP's. They were three-reel slots with 1% and 2% meter movement. Ranges from $25 to $50, $50 to $100, $100 to $250, $250 to $500, $500 to $1000. There was controversy as the ploppies complained about the line pays, and got swarmed by hustlers on the bank when a ripe number developed. After two months Mandalay stripped the MP's out of the place. Bob Dancer even wrote an article about it.
The MP's later came back in other place but the meter movement was even slower than at Mandalay Bay. With most of them today you are lucky if you find .5% meter movement. Liston's charge of $8000 to teach MP's is not a good offer for someone in the USA. But I can see where it would be worth the money in Australia. That is, if they still have five figure jackpots with 5% and 6% meter movement.