Upgrading to a 3BHK in Top Builders: is the premium worth it?

Is the price premium for a 3BHK or villa in the 'Top Builders' corridor really justified now? I'm currently in a 2BHK in Marathahalli, thinking of upgrading. Already have a home loan, so any price jump has to make solid sense for the long run. With all the talk about the proposed tunnel road and metro extensions, it feels like prices there have just exploded. Have people actually seen significant, real appreciation in specific pockets due to these infra projects? Or is it mostly speculative hype? Not sure if the connectivity genuinely changed things for ROI. Would love to hear your experiences and which areas benefited most.