I have been an occasional user of Open Office for a few months. Most of the time is seems to be fairly usable but there are a few niggles.
Embedding videos into Impress is a bit clunky. I don't know whether it is a problem with my version but they play as soon as the slide appears, irrespective of any pauses or 'on-click' actions I set up.
Every time I run Open Office, I get the "R6034" error, informing me that the application has tried to load the C libraries incorrectly. Again I don't know whether this is just my machine or whether it is a common problem. A brief ATFG (Ask The F_ing Google) doesn't help.