I have been using OmniWeb for over five years as my primary web browser. There was a time when I tried Safari, but at that point Safari was too unstable. Mozilla too has good points. But overall usability of OmniWeb has kept me using it. The new 5.5 beta is at least much faster that 5.1. About stability I can't say much yet. Have to test some more. But the browser definetely looks good.