From hopeful spins to honest expectations
Choosing how long to play is up to you, yet no one can tell when the bonus round will land. How often the free spins come is not known in advance, and the result of one session is random whatever the RTP. Past rounds do not change the next spin, so a quiet stretch tells you nothing about what comes next.
Deciding whether a version suits your play starts with the game rules, since only they show which RTP is running. The rules name the version in use, so read them before you bet. Each version's payback figure is listed in the figures table on this page.
Setting your bet means knowing the ceiling, which is x10,000 of your stake. That top prize is reached very rarely, so treat it as a limit rather than a target. Nobody can count on it, and a session with no big hit is an ordinary outcome.