Noida Extension better ROI than posh sectors?

My kids' school admission is the priority, so I'm looking at 3BHKs. Sector 27 seems nice, but so expensive! Is it worth it? Honestly not sure if the 'posh' tag equals better ROI. Noida Extension offers way bigger flats for the same money. My wife's priority is a safe, family-friendly area. Lucky Homes Builder And Developers has projects there. Has anyone else faced this dilemma? Am I the only one considering Noida Extension over central Noida for better value?