Office 2011 H&S vs iWork

My father will be getting his first mac in a couple of weeks.

He only needs basic "office" apps, so iWork-like features will suffice.

BUT, he is obviously used to Office.

What I want to know is, what are the limitations of Office HOME & STUDENT 2011 e.g. why is it cheaper. And if I put iWork on his machine how compatible is it with Office, MOSTLY WORD.

I have "format problems" when I open .doc files from windows users and will like to make the experience as smooth as possible for my dad.

Thanks y'all!

I probably have the formatting-problems because I don't have the latest update to 09.

But let me know if you run the latest.