Which brand is the most compatible 64gb ram for the late 2015 27' iMac with 5k display? Some say that the owc ones are the best, and crucial is second, but i've heard a few cases about the owc 64ram combo(4x16) being faulty or causing the imac to not turn on and other long term problems. On the other hand, some say that crucial's ram are very unreliable and that they even pulled it off the market. Any idea guys?