Double down studs have been at Bally's for the decade I've been going there, some in the Little Joe VP Parlor in WWWest and a bank of six progressives in Bally's proper near the tower elevators. These are all quarter machines. 10-coin play after doubling provides a progressive rf payout starting at $5000 at which the expected return is about 98%. The rf payoff has to get to about $12000 to raise the er to 99%. It rarely gets that high. But watch the pay table. For example, at Resorts a few years ago they introduced double down paying only 1 coin return for a pair of Jacks instead of 2 as in Bally's.
Alan.
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