Haven't tried MS Office 2007 - been using OpenOffice for the last 5'ish years (but you probably figured that already) so I don't feel I need to. OpenOffice certainly does everything I need it to do, has built-in export to PDF (very useful for sending out electronic invoices) and for some reason it seems to have a more elegant layout engine.
It has it's own quirks that you need to get past, but the built-in help is fairly good.
It has it's own quirks that you need to get past, but the built-in help is fairly good.