Best way to maximize a 'casino guru bonus' without getting stuck in wagering requirements?

I've been doing some research on online casinos and I keep seeing these 'guru' bonuses advertised, which sound amazing. However, I'm really worried about the fine print, especially the rollover requirements. Does anyone have experience with a specific bonus that actually pays out, or are they all designed to keep you playing forever? I'm looking for advice on which types of bonuses are genuinely good value and which ones are just bait. Any tips on reading the T&Cs before claiming are greatly appreciated.