Noida builder promises vs reality: huge gap or am I wrong?

Currently in a 2BHK in Sector 75, thinking of upgrading to a 3BHK. Did site visits to a couple of projects by different builders. The amenities they promise are amazing, but how much of that actually materializes? Heard some stories about delayed possession and missing amenities. Also, customer service after booking is a big worry. Is it worth paying a premium for these builders, or should I stick with smaller, local ones? Has anyone else faced this?