Save yourself the hassle and pay the extra money by getting this from the official apple store. On the very first start up while the progress bar was loading, the screen went weirdly green/static for 1-2 seconds then went back to normal, I let that go and thought that maybe it was just an odd occurrence. I just kept using my laptop normally for the rest of the day. The next day i was using iMovie for the first time ever and after importing a video that I received via airdrop  i noticed that the sound was messed up. I'd recommend just buying this from the official apple website / the apple store