Is PS Group overrated or underrated?

I have my masi's house in Kolkata, and visited every year during childhood. I visited Kolkata recently after almost 8 years, and saw a lot of big apartments, complexes, etc. and most of them are being built by PS Group. Is PS Group the biggest real estate development company in Kolkata? How did they build so many buildings? Any political connections? etc. Also, are they overrated or underrated? i.e. are their flats/ projects worth for the price?