Xperia Z2 or Xperia M4 Auqa dual, which one should I buy?

[AC Question]

xperia z2 or xperia m4 auqa dual, which one should I buy?

I want a better quality phone, with better battery backup and I want good quality in screen and camera. is there any major or decision changing difference between both phone's camera and screen quality? which one you will recommend me on the basis of battery, quality, [screen and camera(if not having major difference)]