I love my macbook retina, but I'm so dissapointed with the battery life. NEVER have I gotten over 6 hours and I always am on 60% brightness. I notice I lose a few percent battery every 10 minutes. My Macbook Pro Retina had way better battery, I've noticed I'm plugging this in 2-3 times a day because it get's so low. I know lots of people's batteries are bad, is this an actual fault or just what I can expect for the next 3 years?