It is actually a very unique computing device. Likely the most unique since the original iMacs in the late 90s.
I’m glad MS stuck with it, despite tech bloggers doing there best to trash it. My sister owns a first gen, and loves it for her work. A bit too pricy for me right now though.
I sure hope your sister can upgrade to a Windows 10 version next year without having to buy a new Surface Pro.
Love my pro 3 and I just bought one for the wife for Christmas.
They are not so pricey anymore. They just took $100 of the price so that the i3 core (which is good enough for most things) starts at $699. You can find deals beyond that as well.