Bla, you are obviously one of those über-happy Apple customers that post all over the internet.
You said it was perfect and I just don't see it. If they need PowerPoint, Premiere etc they need Windows or OSX, sure. If they want to play big budget games they need Windows and OSX isn't perfect anymore.
If like most people they just want to surf the web, write letters and manage their photos and they don't want to be bothered with updates and viruses they can run Linux just fine. A properly setup Linux box is the most worry-free computer you will find, no terminals involved. So I can also claim it is perfection, can I? My extended family is proof. I had no instabilities on good hardware ( where are your bugreports? :-P I want to see evidence)