well.. I actually use Kingsoft for my second office programs.
as far as now, Kingsoft does good and I like it much better than Open office (I have never tried LibreOffice so I won't bother saying). Kingsoft does not eat up your memory like Open Office does (when I used Open office, it ate up my RAM and hard disk - and I never use it again ever since). Maybe you have known from what you have read, but IMO Kingsoft has it plus - it can open multiple documents in one window with its multiple tabs feature. as a college student who's currently writing her thesis, this helps me a lot
otherwise, the features are standards, just the same with any alternative office applications. you can change the UI of Kingsoft with your choice of themes, too, even though on the free version, you have very limited choice (as expected, after all).
it's just my experience using Kingsoft (I still have it on my laptop and never intended to uninstall it
), but last decision is always up to you.