Early 2011 13" MacBook Pro, 512GB SSD and 10GB RAM upgrades, macOS 10.12.2 I'm only seeing 4-1/2 tops hours of normal web browsing (Facebook, forums, etc) in Safari. Flash is not installed. KaBlock ad-blocker is my only extension. No bluetooth, no sharing services, minimal keyboard and display brightness, and Dropbox is my only 3rd-party background process. Limited iCloud syncing enabled. I keep this thing running pretty efficiently. Back in the OSX 10.7 days I was regularly seeing 7 hours, which is what it was rated for. Now after five and a half years my battery is at 584 cycles, and coconutBattery says 85% health remaining, but 4 hours is my norm. Am I likely to see any improvement with a new battery, or is Sierra just not optimized for this old hardware? No, I'm not going off the "time remaining" thing, which doesn't even exist anymore. A well-rated aftermarket battery is $60 ish on Amazon right now. All you experts, am I likely to see any meaningful difference?