So I bought new macbook air 13" with 256gb SSD and I have serious battery life problems. At best I got 4.5h but regularly I keep getting 2-3.5h only with normal use (Facebook, youtube, mail and stuff). There are also some dead pixels almost in middle of the screen and it's very annoying. It's been 8 days since I bought the machine so could these kind of problems to be considered as a DOA?