The most popular form of roulette is European roulette, which has one zero, both inside and outside bets, and a payoff of 35:1 on a Straight-Up bet. The XL version retains this feature, which is a big reason why purists enjoy the game so much. The theoretical return to player is 97.3%, with maximum payouts of 50x to 500x the wager. If you're not familiar with European Roulette, that's the version on which this game is based.