Right there with you on "citation needed". I use my Macbooks day in and day out for mass-scale storage administration, and have found the build quality and longevity exceptional compared to the dozen or so HP, Dell, Lenovo, and Toshiba laptops I've owned over the past decade.
1. The batteries last longer: 3+ years instead of the 1-2 years typical of every other laptop I've ever owned since laptops went to Lithium instead of NiMH.
2. The keyboards hold up under my hands, while the Toshiba, Dell, and HP nearby -- all newer than the macbook I'm typing on, by the way -- are all sidelined with keyboard problems, doing duty as servers or using an external monitor and keyboard for my kids to do their homework and play Minecraft.
3. The underlying OS is UNIX. I've been using Linux as my primary desktop operating system since 1998. OSX -- with the addition of a few GNU utilities -- has a very usable CLI and I feel right at home.
I bought my wife a Macbook in early 2007. Other than the superficial cracking on the thin plastic where you open the unit (endemic to that generation of white Macbook), it has performed great. I liked hers so much that in 2010 I picked up a 2007 Macbook myself, and am typing on it while taking a break from coding a routine to handle some mass changes on a farm of hundreds of storage appliances. I type all day, every day, and my Macbook does about half that work.
Please provide more details on the "empirical testing" of ASUS and Lenovo. If they truly are longer-lasting than my two six-year-old Macbooks which have been worth at least three Windows-based laptops apiece, then I am extremely interested. It's the amazing reliability of Apple's products that drew me to them. I don't need latest, greatest, or shiny anymore. I need reliable, reasonably quick, and comfortable to use.