Bonus terms being genuinely fair rather than just appearing fair upfront is something that only becomes clear after actually playing through them. Key things worth checking are the wagering multiplier, game contribution rates, maximum bet restrictions while a bonus is active and any cap on withdrawable winnings from bonus funds. Sites that make all of that easy to find and clearly written are generally the ones where the reality matches the impression — the ones burying important conditions tend to have other friction points worth knowing about before depositing