Most Windows 8 RT/store apps still have a way to go to be as mature as their iOS counterparts. Having used it regularly on a tablet for 8+ months the mail and IE apps are not full-featured and often a source of frustration, even printing a pdf the way I wanted required a visit to the desktop app. They'll probably get there eventually but in the meantime at least I can flip to desktop mode to get those features I know and love.
I like the W8 whole charms context-sensitive thing and can see that being more popular once people get their heads round it. Tricky thing is I would still recommend iOS to the man in the street, but give W8 time.
As you say, these mobile OSes all do the essentials well enough, like hot drinks it just comes down to which you prefer (or are used to), coffee, tea or hot chocolate?
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