In my experience (because of my work I have macbooks, linux machines and a windows machine), linux with i3 beats mac os x and windows on battery life by a (very) large margin; in some cases 3x (for instance on x220 2011 with 9 cell, I get 4 hrs under windows and 15 under linux/i3) with the same workload. Obviously I run the Linux battery tools, but so do the other OSs their own.

i3 here is the ‘magic’ part because with other, more mac/windows like window managers, the battery life is comparable, however, I cannot turn those off on mac/win so I cannot test if that is really the case. But if I use, say, unity, the battery life drops to at or below what it does with it’s native system.

> And battery issues?

And issues of not being able to run software (often from Adobe) that are required for work.

MacBook Pros definitely don't have a great battery life.