First time buyer in Gurgaon: What's the real possession story?

Since last year I've been so fed up of renting, landlord ne rent badha diya fir se. Finally taking the plunge, EMI vs rent math ab sahi lag raha hai. But yaar, Gurgaon mein projects ka possession delay kitna common hai? I'm looking at Vatika The Seven Lamps, suna hai kaafi projects mein builders time pe delivery nahi dete. Kitna actual delay expect karna chahiye vs promised? Kisi ka experience hai yahan? Aur jab finally possession milta hai, quality issues kitne milte hain? Snag list mein kya kya nikalta hai? Builder fix karte hain ya bas taal dete hain? Aur registry experience kaisa rehta hai? Suna hai kaafi visits lagte hain aur 'unofficial demand' bhi hoti hai. Koi bata sakta hai apna experience? Should I go for RTM instead? Not sure about this whole process.