I was strictly an iWork user for 4 years. Two months ago, I got a 3-device license for MS Office for my new MBA, as one of my kids uses it for school and he is REQUIRED to turn in an Office document (vs. pdf) and over the years I have had trouble with iWork exporting to .doc files without messing up. So, if you are in an environment where you need to share or need 100% compatibility for MS Office, go for Office. Be forewarned though - it is ugly on the Mac. I like it on my work Windows machine, but really dislike it on the Mac.