Higher floor or resale deal: Gurgaon dilemma

Since January I've been shortlisting 3BHK flats in Gurgaon, near DLF Phase 3 for my kids' school. Floor-rise premium aur PLC ka concept samajh nahi aa raha. Builders like SS Group charge so much for higher floors. Is it worth it for end-use? My wife thinks lower floors are safer. Also, secondary market mein deals better milte hain kya? Can we negotiate more on resale than new? Any tips on negotiating these charges ya resale market ka experience? Hope this helps someone.