MacBook Air 13" Mid 2011 Repairability: 4 out of 10 (10 is easiest to repair).

Once you manage to take off the bottom cover, all the parts are pretty easily replaceable.

Opening the bottom cover is quite difficult if you don't have the right screwdriver. It's clear that Apple didn't want people to open their machine.

All the components -- including RAM and SSD -- are proprietary, meaning that no off-the-shelf parts will work in it without serious rigging.