My rating of the browsers above is based on the ability of the browser to render a page. When I sign in my hours to get paid for the week, I need the browser to render the well. If items are missing on the website, I must use another browser. Once I find the browser that renders the employers webpage, I can safely say this is a good browser.
Sometimes I simply use IE. I need to get paid, for hours worked. Ya-digg? Pure and simple.
I've tried all the browsers for the Mac and I would say the best is probably Safari, but I think Camino is well worth a look. It's built on the Gecko layout engine used by and developed by Mozilla, but it used the native Cocoa API's, as opposed to the XUL interface used by most other Mozilla products. From a user perspective this just means you get a browser that is more consistent with the wider Mac OS experience. It also integrates well with Mac OS features such as Keychain Access. As it's built on Gecko it is also open source, so if it takes your fancy you can play around with the code - if that's your bag - or enjoy the benefits of a developer community who are constantly developing and improving the browser.
Try a few browsers out - there really is no BEST browser - just find the one that suits your needs and uses best. After all, they're free.
If your looking for the fastest Mac browser, you can see how they performed in this Best Mac Browser Shootout. The shootout benchmarks the top ten Mac browsers for rendering performance.
I have used Safari since it first became available. That is until I tried Chromium. I find I like Chromium much better. It is very fast and uses way less resources then Safari.