I use NeoOffice on the Mac and it’s awfully slow. Unless the Linux OpenOffice version performs better, they’ve still got a little work to do. In the past the problem has always been document archives and formatting - alternate office suites never quite render the tables and headers in those older Word documents correctly, and most businesses consider that a deal-breaker.
I haven't noticed any performance issues, course this new box is a Phenom Quad with 4GB, so who knows? I'm on v3.0.0 build 9358 and I've had zero problems with tables or headers/footers, of which probably 50% of my docs have one or the other. My problems are with usability/features. Like in Word, I often search for non printing characters in the search and replace dialog. Tabs are "^t", para marks are "^p", etc. Writer doesn't allow you to do that. The drag-and-drop is significantly more awkward in Calc than in Excel, as well. Annoying little things like that.
NeoOffice is much slower than open office still not terrible but it works