A big shout-out to Safari which used by far the least amount of memory to present the same nine tabs. If you're working on a computer with only 512MB or 1GB of system memory, its spend-thrift ways might come in handy.
However, if I had to pick just one to keep on my system, it would be Firefox. It's fast enough, it has the slickest interface, it uses considerably less memory than Chrome, IE, and Opera, and it's just generally the easiest to use.
Performance and memory usage may be moot if your needs extend beyond the ordinary, in which case the browser you choose as your mainstay may come down to add-ons.
Fortunately, as all the browsers we tested are competent, free and export and import bookmarks, you can use any, or all of them. Yes, life is good in the browser world.
Sign up for CIO Asia eNewsletters.