Some people reported absolutely abysmal speed in IE6 and with big (as in: >50KB) docs even in Firefox. Turns out the CountChars plugin was solely responsible for this:
http://xinha.python-hosting.com/ticket/655 I disabled it and now I can edit and scroll in huge documents (as in 100K HTML) in Firefox just fine. And even IE6 now works quite acceptably.
So in case you were wondering about the performance, grab the latest SVN! Or test
here if you're skeptical of such extreme claims.
Gabriel
Warning: Current Xinha version is broken on IE
Maybe you want to wait if you want to use IE. Because the current version keeps crashing my IE occasionally.