It really depends on the needs and interests of the individuals in question. There are many people who like the idea of a *nix system, but don't want to fidget with sources, for reasons of time management, to get installations to work correctly so they run with a windows system. Conversely, there are those that have all the time in the world but not the inclination to learn anything about the computers.
Each of the platforms has their advantages including variations in stability, security, scalability, etc. The only way to know who would get what would be to take all these things into consideration and then adapt the OS to that individual.

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Ms Mittens is also correct in her assertion that comfort has a lot to do with it. I am most comfortable in a *nix environment where as many of my peers won't touch it. It's for the better really. How much are each of these individuals willing to go through to see what the differences are and why someone would chose one over another?
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