Random spins against any promised return
Deciding to keep playing until the bonus appears means accepting an unknown wait. How often the bonus round comes is not known in advance. The result of one session is random, whatever the RTP printed in the rules. Earlier spins do not change what the next spin pays.
Checking the RTP version before the first spin means opening the game rules. Only the rules show which version this lobby runs, so the rules are the place to confirm it. Compare two titles by their rules, not by memory of earlier sessions.
Deciding how much to stake for a large prize means reading the maximum win as a ceiling, not a target. The maximum win of Bigger Bass Bonanza is a ceiling reached very rarely. A free spins round is capped at that limit, however many features line up.