From what I know the entire purpose of the Macbook "Pro" line is literally that they're made to be modular. They were at least. I maintain a 2011 Pro. The build quality is noticeably nicer than the cheaper chassis they produce today. The experience itself is actually much nicer too, smoother, feels better. Added, modern displays have great resolution. But the aged units carry an interesting and rich in depth projection ability you don't find today.