Macs lasting longer than PCs is generally a myth. Usally perpetuated by those that want to help justify the £1400 outlay to the wife and family over the £600 box the kids wanted to play BF4 on. The biggest killer of any computer is usually human stupidity than component fails. And then again the components whether Mac or PC are still all made by FoxConn.
It's only the case and OS that's different at the the end of the day.
I remember the folks I used to give Mac gear jobs to (before they went under) had plenty of people queuing round the block with faulty Apple gear.