Why? I thought Chromium was supposed to be the open source (libre) version of Google Chrome. It shouldn't do anything "evil". I guess you would have to change the search engine and perhaps disable update checking if you plan to do that yourself, but other than that...

I personally prefer Firefox regardless, but that's not because of paranoia reasons (I just like it better with about:config and the available add-ons and the way the url bar works and... just usability reasons).