Under-construction vs ready-to-move in Narsingi — what's the real savings?

Wife and I are looking for a 2BHK around Narsingi area. Visited few projects last weekend. The under construction ones are quoting around 9000 per sqft and saying possession by 2028, but then there is GST and all that extra charges. Ready to move flats in the same belt or nearby gated communities are asking like 10500 or 11000 base price but we can move in immediately and save on our current 35k rent in Kondapur. When I calculate the pre-EMIs plus paying rent for next two years, that 15% savings on under construction seems to completely disappear. Plus you never know if they will actually deliver on time, heard so many stories about possession getting delayed by a year or more. For anyone who bought under construction in Narsingi recently, did you actually end up saving anything at the end or is it better to just buy a resale/ready flat and avoid the headache? What would you do?