I switched from Crossover Office to VMWare for my Microsoft Office business on my computer yesterday.
I use Ubuntu Linux on my personal laptop, and for my work I must have Microsoft Office installed. I first tried using Crossover Office, and it seemed to work great for the first time. Crossover Office is a Win32 sublayer, just like Wine and Cedega, that lets you run Windows applications seamlessy inside Linux. After a while, I got to notice a few bugs that meant the end of my Crossover journey. It was impossible to open a few spreadsheets because of a few missing API:s, and sometimes the ALT key would hang because of my window manager. I cannot afford having a bug-ridden version of Office, so therefore I had to acquire VMWare Workstation 5.5, in which I have installed Windows XP and Office 2002. I am impressed by the performance; despite the fact that I only have 512 MB of RAM, it works like a charm.